I'd recommend Karl 100%. Karl is a very rare modern gunsmith in the sense that he does EVERYTHING on your project, unless you want some custom finish he doesn't do in shop or engraving. You would be surprised at the shops that people think are one-man shops that aren't. Most of them farm out almost every aspect of the job to other "sub contractors". Not Karl.
I currenty own 4 S&W revolvers worked over by Karl to different levels. One 5" 625 that I had him just chamfer the chambers and slick out the action a little. Also an early 6" 686 that was one of the first handguns he ever built when he began doing gunsmithing work that my father had built as a pin and plate gun.
The other two are carry K-frames. I had him build me a 3" M13 and a P&R 2-1/2" M66.
The M13 was an ex-French police trade-in reimported by Century Arms. It was definately dropped more than fired (it is French) and the front sight was bent in a few directions. I had Karl mill off the sight and dovetail in a Millet blank, chamfer the chambers, round the trigger and install an overtravel stop, bob the hammer, slick the action without lightening it (per my request) and dehor every sharp edge. It was extremely beat up so I had Karl bead blast and parkerize it. My friend just bought a Sokol M10 that has his "Mountain Tuff" finish. It's an extremely tough epoxy finish baked on over parkerization, and I'm thinking about sending my M13 back for that treatment since it's really showing it's time spent in a holster and training.
The P&R M66, no dash, was bought from a local cop and had some honest finish wear, but not abused at all. I had Karl do pretty much the same mods to that one as the M13, but since it's recessed, he didn't do anything to the chambers. The front sight wasn't damaged, so I just had him run a dovetail mill through it and add an orange inlay. For a finish, I had him bead blast it after a full dehorning treatment. Both of them wear hard nylon grips.
I've known Karl since before he opened his first shop. We both grew up in the same small farm town in W. MA. Back when I was younger, we could get our LTC's in MA at 18, but we couldn't buy a handgun until 21 per federal law. So I was carrying one of my father's handguns from 18 until I turned 21. On my 21's birthday, Karl built me my first handgun that I personally owned. It was a 3" M65 that I bought new from him. Karl chamfered the chambers, slicked the action, bobbed the hammer, installed the orange inlay in the front sight and put on the same hard nylon grips I still use. I can't even guess how many rounds of my max cast bullet .357mag reloads I fired out of it (in my younger days, I felt that every round I fired had to be max. I've "matured" out of that) and I really shot it loose. It had some flame cutting on the face of the cylinder and on the topstrap. I traded it away in a weak moment and still regret it. If someone has a custom 3" M65, fairly worn, SN BPS 1861, I'd like to buy it back! Honestly, it felt good shooting enough to wear a gun out!
My friends have several Sokol customs, too. Several S&W revolvers, a few BHP's, some .45acp 1911's, and a nice SA 9mm 1911. He's working on a custom Commander sized .357 Sig 1911 that I got to try out last summer. Nice gun. Karl also did an action job on a Winchester Trapper Carbine for me a few years back, too.
Here are my two current S&W K-frames. You can't go wrong with him. Let us know what you decide.