Hi Kevin, I use 52, 56, and 60 degrees find they are enough. I bought the new tokomo’s and great quality. Saying that I’ve switched all my irons, great value and the quality is superb.
I’ve still got my ping 430s but use the Tokomo’s all the time now.
I would say it really depends on what irons you have and what loft they are, but in general you want 4 degrees of loft gap minimum. My PW is 46* and AW is 50*, so I have a 54* and a 58* Vokey. You could probably get away with a 56* as your highest lofted wedge if you are a higher handicap like me, I only have a 58* because it gives me a nice gap for full shots from the 54*. I would recommend your highest lofted wedge have a forgiving bounce/grind for bunkers, and maybe get a different grind/bounce for versatility on your other club e.g. one for tight lies.
I play Mizuno irons & wedges. Recently swapped out my MP243 GW for the same loft in a T1. They’re really good but as others have said it depends what feels good to you. The shop at our range has second hand ones that you can hit a few with. Not sure if you have anything similar nearby but that could give you a feel about the clubs and then you can decide new or used. For info I have 48, 54, 60 in the bag. 60 for bunker and (attempted) flops, 54 for 100 yds all the way to chipping (it’s the multi-tool).
If you play cavity back irons it makes sense to use cavity back wedges as I do. I switched from vokey (blade style) to Cleveland CBX (forgiving) and my striking and distance control became much more consistent. I carry just two specialist wedges 52 and 58 which is plenty for me as I can cover a range of yardages by varying tempo and length of swing.