I just spoke to Mark a few days ago about a 28-2 .41 mag conversion that I want him to do. He's doing well and taking work. He's a top notch revolversmith, as good as you'll find.
I had him do a 9mm conversion and some other work on my 360J back in 2008 when they first came out, sent it back to him a year or two ago to have a titanium .38spl cylinder fit to it to make it a convertible. I've carried that gun as a BUG, off duty, you name it, and it's been great, he turned it into exactly what I'd been looking for.
A few years ago he also did some repair work and a tune up on an Austin Behlert 25-2 snubby I had. Mark is the only 'smith I'd trust with that gun and, again, his work was impeccable.
This week I'll be sending him a semi-beater 28-2 along with a titanium .41 mag cylinder and a 4" 58 barrel. He's going to turn all that into a round butt 3" .41 mag hot rod for me, I'll probably have it hard chromed so it'll look something like 3" M65 on steroids.
I would not hesitate to have Mark do any custom or repair work on any revolver. I suggest that if you want to get hold of him you call because he is slow to answer emails. He's a one man shop and sometimes you have to try a few times to get him but his work is worth the effort.