I've carried both, a 642 and either a 3" 65 or a 2" 64. Significant difference between them, but the Airweight frame is a major part of that.
With the right gear, either can be carried easily. When I had the 65 I typically carried it in either a Milt Sparks Summer Special II or a VMII-style holster by another maker. I usually carried the 64 in the same holsters. Belt was a 1.5" double-layer bullhide Beltman. I could carry either gun for 12+ hours/day without a problem.
Most of the time I've carried the 642 as a primary/only gun it was in a Side Guard Holsters Quick Clip IWB holster. Much easier to carry and conceal than my K-frames. I currently carry it as a BUG in a Wilderness Tactical Renegade ankle holster. I will rarely pocket carry it, but when I do it's usually in a DeSantis Nemesis holster, sometimes in a Blue Force Gear pocket holster. To me, that's the big advantage of a J-frame snub over a K-frame, carry versatility. I'm pretty sure I don't want to try carrying a steel K-frame in either a pocket or ankle holster.
In my experience, what CB3 mentioned about barrel length and stability is partially true. For example, my current EDC is a Beretta PX4 Compact, but I've found that carrying it in a Kramer IWB #3 holster for a full-size PX4 improves stability and comfort.
However, particularly with revolvers, I think holster design plays a more important role than barrel length. I've only carried IWB, but I think the same could apply for OWB. What I've found is that having the revolver's cylinder paralleling the belt provides sufficient stability regardless of barrel length (within reason, of course). Remember that the mass of a revolver is concentrated in the cylinder, its center of gravity. Having that positioned at belt level (or possibly lower) stabilizes the gun better than a higher-riding holster. It might be different for AIWB, where having the barrel long enough to lever the grip into your body can be a comfort/concealability factor.
Also, stating the obvious, everybody's different, so what works for me may or may not work for you.
Just my opinion.