That would be a nice conversion.
When I was doing my research on this recent conversion, someone on one of the gun forums was bragging about his 625 conversion. Piece of cake, and cheap; If I remember correctly all he had to do was rent a reamer and in a half hour, he was done.
I’ve had a 460 Rowland Carbine upper conversion for a couple of years, and it is a lot of fun, yet suitable for serious purposes too.. After my last campout in an area that is posted for bad bears, and I didn’t want to carry my six pound .454 around, I decided rather than spend a thousand bucks or more on a more compact .454 or .44 Mag or a Ruger .45LC capable of ++P pressures, I’d go ahead and spend the $300 on the Rowland conversion.
After a bit of frustration, I got it to where I trust it in any situation, short of an angry Grizzly or Kodiak....
I’ve seen that upper conversion on the web, looks like a hoot to shoot!
All we have is black bear and mountain lions, I decided 10mm was adequate for what we have around here and quit worrying. Before I bought the G20, I did work up some pretty stout 45 super loads for the 625. I had some 255 grain bullets over 1100fps, but I was afraid some of them would eventually find their way into one of the autos so I shot them up and bought the 10mm. Even with 15 rounds the G20 is lighter and more compact.