The Mizuno Pro M-15 and Srixon ZXi5+ delivered remarkably similar results in our head-to-head test. Ball speed was identical, carry distance differed by only two yards, and their average landing angles were almost the same.
Ross gave the Srixon the overall win because of its lower price—not because it produced a substantial performance advantage.
There is another important detail: neither iron was his preferred fit for the delivery demonstrated.
If you are comparing these irons, the useful question is how their differences in flight, appearance, feel and cost relate to your game.
Watch Our Mizuno M-15 vs Srixon ZXi5+ Comparison
Watch the full comparison on the EP Golf Studios YouTube channel.
Ross tested both irons at approximately 80mph clubhead speed using the same shaft, then compared their performance alongside his preferences for appearance and feel.
How Were the Irons Tested?
Ross explains that he hit approximately 15–20 shots with each iron.
The average clubhead speeds were within 0.3mph, with comparable strike locations and identical average efficiency. That provides useful context for the results: a large swing-speed difference was not responsible for one club travelling further.
The same shaft was used in both heads. However, the video does not confirm that their measured lofts were equalised, so this should be treated as a comparison of the tested setups rather than an isolated test of head design.
What Did We Compare?
The review considered:
Ball speed and efficiency.
Launch and backspin.
Carry distance.
Peak height and descent angle.
Consistency across the shot sets.
Appearance, feel and forgiveness.
Price and overall value.
The numbers describe Ross’s results in this session. They are useful comparison evidence, rather than a prediction of what every golfer will achieve.
Mizuno M-15 vs Srixon ZXi5+: The Results
Average clubhead speed - both around 80mph
Average ball speed - identical
Average efficiency - identical
Launch = Mizuno slightly lower
Backspin - Srizon 400-500 rpm lower
Average carry = Srixon 2 yards further
Average Peak Height - Srixon 2 feet higher
Average descent angle - almost identical
UK Prices - Mizuno at £230 per club, Srixon at £175 per club
Prices are those quoted in the video, references costs at the time, rather than a current retail price check.
Distance: Just Two Yards Separated Them
Several of the shots shown carried approximately 160 yards with either iron at around 80mph clubhead speed.
Across the larger sets, the Srixon finished two yards ahead on average.
That is a small difference, particularly when average ball speed was identical. Ross described the overall performance as effectively level.
For a golfer choosing between them, those two yards need to be considered alongside the required distance gaps and the rest of the ball flight. They do not establish a clear overall winner by themselves.
Launch and Spin: A Different Route to a Similar Flight
The Srixon launched slightly higher while producing approximately 400–500rpm less backspin.
Ross preferred its slightly higher launch for the swing speed demonstrated. But the final flight measurements were very close:
Mizuno: 76-foot peak height and 42.1° descent angle.
Srixon: 78-foot peak height and 42.2° descent angle.
Those figures show why it helps to consider the complete flight.
A higher launch does not automatically produce a substantially steeper landing angle. Likewise, lower spin is not automatically an advantage in an iron.
Which Spin Profile Would Suit You?
In this comparison, the Mizuno provided more spin. The Srixon provided less.
Whether that difference is helpful depends on the golfer’s delivery and the flight they need.
Ross also raises ball choice as another fitting variable that can influence spin. The practical point is to assess the club and ball together, rather than choosing an iron from one measurement in isolation.
Forgiveness and Consistency: No Clear Separation
Ross rated forgiveness as a dead heat and described both irons positively.
He also noted tight standard deviations across the data. In plain language, the results within each set were closely grouped.
That is encouraging, but the comparison does not establish identical forgiveness for every golfer or every impact location. Ross’s strikes were comparable during this session, and his assessment reflected what he observed.
If your typical miss differs from his, testing your own strike pattern remains important.
Appearance: Mizuno at Address, Srixon From the Back
Ross preferred the Mizuno when looking down at the club behind the ball.
He described it as slightly slimmer and nicer to his eye.
Looking at the back of the heads, however, he narrowly preferred the Srixon’s appearance. Both decisions were close.
These preferences are subjective, but they still belong in a fitting. You should be comfortable with the club you are preparing to hit.
A small visual preference might matter more to you than a two-yard difference in average carry.
Feel: Srixon Narrowly Edged It
Mizuno’s reputation for feel makes this an interesting part of the comparison.
Ross gave the Srixon a narrow advantage, while stressing that the two were very close.
That was his preference during the test. Another golfer may favour the Mizuno.
The useful takeaway is to approach the comparison with an open mind. Try both and decide what feels better to you, alongside what the data shows.
Price: The Difference That Decided Ross’s Winner
The prices quoted were £230 per club for the Mizuno and approximately £175 for the Srixon.
That is a difference of around £55 per iron.
At those quoted prices, a seven-club set would work out at approximately £1,610 versus £1,225—a £385 difference before any specification changes or other charges.
With performance closely matched, and Ross narrowly favouring the Srixon’s feel, he could not justify the additional cost of the Mizuno for himself.
A golfer who strongly prefers the Mizuno’s appearance or benefits from its higher spin may reach a different conclusion. The extra cost needs to make sense for their priorities and results.
The Important Caveat: Neither Was the Right Fit for This Delivery
Ross explicitly says neither club was suitable for the particular player delivery being demonstrated.
That matters more than the small difference between them.
A comparison winner is not automatically a fitting recommendation. Two clubs can perform similarly while neither produces the flight the golfer needs.
It would therefore be a mistake to turn this review into a rule that an 80mph golfer should buy the Srixon—or the Mizuno.
Swing speed provides context. Your delivery, strike and required ball flight determine whether a head is worth pursuing.
Questions Golfers Are Asking
Which Was Better: Mizuno M-15 or Srixon ZXi5+?
Ross chose the Srixon ZXi5+ because it delivered very similar performance at a lower quoted price. Ball speed was identical, carry differed by two yards, and descent angles were almost equal. He also narrowly preferred the Srixon’s feel. His decision was primarily about value, rather than a substantial advantage in performance.
Did the Srixon ZXi5+ Go Further?
The Srixon carried two yards further on average in this session. Both irons produced individual shots around 160 yards at approximately 80mph clubhead speed. Average ball speed was identical, so the small carry difference should be considered alongside launch, spin and gapping. It does not establish that every golfer will hit the Srixon further.
Which Iron Produced More Spin?
The Mizuno M-15 produced approximately 400–500rpm more backspin in the comparison. The Srixon launched slightly higher, while peak height and descent angle remained very similar. More spin may be useful for one golfer and unnecessary for another. Testing should establish the flight you need before deciding which result is preferable for your game.
Did the Mizuno Feel Better Than the Srixon?
Ross narrowly preferred the Srixon’s feel, although he described both as very close. He preferred the Mizuno’s appearance at address and the Srixon’s appearance from the back. These are personal judgements. Trying both gives you the opportunity to assess your own preferences alongside the launch-monitor results, rather than relying on brand reputation.
Are These Irons Suitable for an 80mph Swing Speed?
Swing speed alone cannot establish suitability. Although Ross tested at approximately 80mph, he said neither head was suitable for the delivery demonstrated. The review should therefore be used as comparison evidence rather than a fitting prescription. Your strike, delivered loft, launch, spin, landing angle and distance gaps need to be assessed together.
Find the Right Irons for Your Game
At EP Golf Studios in Newbury, Berkshire, we benchmark your current clubs, test alternatives and explain the results.
The aim is to identify a worthwhile improvement and help you understand why a particular specification works.
If your existing clubs remain the better choice, we will tell you.
