I had a fitting for 2 new SM6 last weekend - the first time I have been fit for wedges and it certainly won't be the last. I had 2 old Miz wedges in a 50 and 54 as well as a 60 SM5 all of which have served me well and, to be honest, I did not think needed changing.
The fitting showed me that the gapping was slightly uneven in terms of my PW when compared to the 50 and then the 50 compared to the 54. But the surprising thing is that I have gone for a 50 and 54 again with the same bounce - the fitter told me that gapping was improved as the lofts on the Miz had probably weakened over time. He was going to test them on the loft and lie machine at the end but I forgot.
So I have 2 new wedges on the way with my kids names stamped on them but I am under strict instructions to hand them over for wrapping and I can't use them until Christmas!!