I have one
Carries nicely. Very light and compact. Great for pocket carry. That's what I bought mine for. Was originally looking at a Ruger LCR but I found it 'bulkier' in a side by side comparison. My 637's trigger was stiffer than the LCR when comparing the two out of the box but it smoothed out nicely with snap caps and shooting. I'll never understand why people get a trigger job on brand new handguns when snap caps are cheaper. Have to at least find out if the thing will smooth out before throwing money into it!
Right now I'm working on finding the perfect grip set-up(for me). The boot grips are OK, but I'd like to get a little bit of my pinky finger on it. I have factory magnas and a Pachmayr adapter arriving in the mail soon. Hopefully, that'll be the cure.
The revolver shoots well. I'm not as good with it as my Speed Six but I haven't had it that long. Still playing with types of ammo. Very snappy with +Ps. And I'm not a recoil shy person. The next grips should make a difference. There's my take on the 637 for good or bad. Overall, I like mine very much.