Played with a former pro (mp-60s in his bag) and one of the top Ams around here (mp-62s) today and we talked a bit about mizzy irons.. and equipment in general..
The best players I know rarely change irons.. Think you need to get a set of great quality forged irons (mizuno certainly is on that list) that you like you looks of, get them fit and make sure you cover the distance gaps with your bag, practice your short game and go play.. no need to change anything unless you want to spend time getting used to some new stuff.. the pro says it takes 2-3000 balls to get used to a new club.. not sure where science fits into that declaration but swingweight and lie/loft, balance, bounce, offset etc all are a little different and it's a game of inches ..
Had a conversation with an OEM exec this week and he was talking about equipment contracts that the pros have and how difficult it is at times with some Pros to get them to play the "new" stuff like their contracts say they have to do.. he told me about a longtime top pro who just refused to take his older driver out of the bag.. just would not do it.. the OEM changed his contract so he could get the fee associated with the section of his contract that stipulated he play "latest model" driver. Was a lot of money he was willing to not get.
Once asked a national class amateur if he had tried any of the new equipment knowing his irons were about 10 years old and his driver was at least 5. He said, "No. I'm trying to get better." end of discussion..
I hear the new irons are awesome.. see Willy no. 4 dropped his x8 pros for 95s and I have one club champ level friend who has proclaimed them a gift from the gods. He had played the earlier version.. likely would not be too much of a transition from xzy1's.
Have heard an equipment and teaching guru say you need to change your irons at least every two years.. that you wear out the grooves. The best ballstriker around here plays irons he's had almost 20 years.. they are worn away.. no more chrome.. a small little black circle right in the middle of the blade.
Caddied for a one time pro and reinstated amateur who has had the same putter (bulls-eye) for nearly 35 years.. His driver shaft was worn to the filaments and the head was a sub 400cc model. He has a great record in national and International events over many years..
Have another Pro friend who says that unless you are paid to play equipment or just like to spend money and try stuff it makes no sense to swap equipment. I think the exception is the ball.. ball technology changes.. forging is much the same today as when Hogan made irons.. and before.. ya know?
What are you playing this year?