Since MB’s have not really changed significantly over the years, pick up a used set and give them a try for a while. If you decide to go back to the T100, you will still have a great back up set or can sell them for nearly the same amount you got hem for.

I think you answered your own question -
"I have a couple swings here and there get away from me where I am thankful for the forgiveness of the T100! "

Only a minority of pros play MBs anymore. That's another clue. So you should find an outdoor center with the 620 MB 7 iron fitting iron and give it a whirl. If you still have a need more than just a want, then go for it. I always wanted to move from AP1 to AP2, but fittings always showed me why that was not my best choice.

3,4,5 irons are massive difference so would try to get the cb’s or 505’s there. You may get away with 6-9 mb however if not flushed, distance drop off is marked. If you want shiny clubs go for it as they are playable bar the longer irons. I always preferred blades to chunky irons though aware giving up consistent yardages.

If you truly are hitting ball first with a slightly descending blow, the mats aren't really hurting you. If you were a picker swinging a little shallower, then I'd say it's misleading. I've played the forged blades for a long time, just recently gave up the MB's. I find the 100's have a lower flight, as the center of gravity has been moved. My fitter was a Tour guy, knows the ball flights of better players like the back of his hand. He had to pry the CB's out of my hand, claiming there's a reason MOST Tour players have left the full blades. Truth be told, these new forgings are ridiculously soft compared to even 10-15 years ago. Don't sweat looking for the 620's, they look pretty, but you're better off with the T's.

I have full sets of both, most of the time I’ll will play3-5 t100 then 6-9 mb. The biggest difference is distance control, if you flush them both they will be about the same but when your not striking it the way u want u will miss greens short with the mbs

As others have said, since there has not been much change, you can pick up a used set and give them a try. My advice would be, if you are a sweeper, the mbs might work out. If you are a digger, go with the cbs. Best of luck.

They would likely change your game if you are a good ball striker. I’ve been playing mb’s since the 710’s and there is a noticeable difference going back to the 600 series in the 620’s. The sole grind was the biggest adjustment. If you can find a set of 716’s in decent shape they’d likely be a good expirement. I think the 718’s were the start of the sole grind. I went with the combo set 5-6 cb and 7-pw mb. Not a fan of the combo every time I hit my 6 iron I wish I would’ve just went with the mb in it as well. If you’re a righty you can buy single irons cheap to try there’s lots online.