Now I hit a lot of clubs and probably one of the best irons, if not products, of the last 12 months, is the Mizuno JPX850 Forged iron. This added boron into the steel head to strengthen it so they could combine feel and forgiveness with a little extra ball speed.
Not only was it a great performer, but also it was a genuine new technology and I like that sort of stuff. So it was no surprise that the next to get the boron treatment would be an MP iron and here we are with the Mizuno MP-25.
On paper it looks like a sure fire winner, with the Grain Flow Forged 1025 Boron Steel shaped into a cavity back head that is sized to match the current size of the largest MP iron in the range.
Picking one up for the first time and you have to say it looks great and when you put it down at address it sits beautifully behind the ball with the mid-sized head and top line giving the perfect hybrid of blade and cavity back.
It is a different style of construction to the JPX850 Forged, which did feel like an MP iron masquerading in JPX clothing. However put the MP-25 beside it and you can see that it is the true MP descendant, with a slightly more compact look and a closed cavity back.
Compared to previous MP irons, the MP-25 gives a lovely solid feel at impact that is much better than a normal blade and certainly more solid and not as hollow sounding as the JPX850 Forged.
The MP-25 slips through the turf as well as previous MP irons do and the slightly wider sole has a little relief grind across the trailing edge to help it play a little narrower than it actually is.
Beneath the surface of the muscle back lurks a hidden chamber or 'Micro-Slot' pocket cavity in the 3 to 6 irons that apparently is in there to help generate faster ball speeds. It is not in the shorter irons as apparently the benefit is less great, so there is no need for it.
This is because the higher loft results in a more glancing blow so the face does not react in the same way. Without the Micro-Slot, the filled cavity in the 7 to PW has a lower sweet spot than previous MP irons and Mizuno say that bridges any performance gaps.
The Micro-Slot does do its job as on Trackman the MP-25 did generate a little extra ball speed over a fully forged MP-64 iron whilst maintaining the level of feel. I compared the 5-irons at around 83mph and even with a factionally lower clubhead speed, the MP-25 generated over 3 mph more ball speed, which combined with a little extra spin gave an extra 4 yards carry.
Mizuno keep all their MP lofts the same so there is no delofting here to get the greater distance. It's just quality engineering and materials and the Boron Steel allows the forged heads to fight back against the increasing distance from the cranked up springy cast faces of the new style of distance players irons.
Maybe because the JPX850 Forged irons were so good I was possibly expecting too much from the MP-25. If they had just added the Boron Steel to pretty much any MP club I probably would have been all over it, but something holds me back from going gooey over the MP-25.
Having certain materials or head designs in one part of the set and not another always raises eyebrows with me, so the flow of the set is a very slight concern. It is possibly a minor thing, but I have experienced this in other irons with slots or cavities that don't go through the whole set and compared to the MP-5 set, you can notice a slight difference. Whether this matters is really up to you as it is not a deal breaker.
The short irons without the Micro-Slot feel very solid and are a bit firmer at impact with the sort of forged feel you would expect. When the Micro-Slot appears in the 6 iron it does feel different in a good way with a slightly lighter feel and just a touch more zip as the cavity does its job by flexing a little at impact to increase those ball speeds.
Right the way up to the 5-iron is excellent, but I found the 4-iron hard work. The relative level of forgiveness seemed to be marginally less at this stage, so maybe this is the point to blend in the excellent MP-H5 long irons.
If you are between an MP and something larger then I still would recommend trying the JPX850 Forged irons. However, if you are a diehard MP player or play off low single figures then the MP-25 is your perfect shape of iron for feel with a little bit of forgiveness.
The addition of the stronger Boron Steel to the MP line really makes the MP-25 stand out from the pack in the forged better player category, so give it a try and see if the MP-25 can strengthen your game.