My 642 is flawlessly fitted and finished. I hear about some that aren't, but mine is. Works perfectly, too, and I can keep 'em on paper on a small target at 25 yards.
I tried a Scandium .357 before I bought my .38+P. I didn't think I'd ever load the light gun with .357 rounds for self-defense, and it wasn't fun (left my hand bruised for a few days). I CAN shoot it, but I don't think it makes sense in a self-defense situation. For one thing, part of the reason I like DA revolvers is that I can shoot them one-handed with no concern for "limp-wristing", in any position, with no controls to concern myself with.
So I saved my money and got a 642. Love it. Used the extra money towards a used but excellent Model 60 -- that little extra heft and I can shoot .357s in it, no problem.
I can choose to carry the 642 with .38+P, or the 60 with .357, and I have no qualms about shooting either one accurately and quickly. I even pocket carry the 60 occasionally, but usually it's a concealed city/trail gun for me in an IWB holster, or an OC trail gun that doesn't get in the way.
Those ultralight Magnums make little sense to me. If they were 50 bucks extra, I might have gone for one and loaded it with .38+P, but they're not.
The bottom line? A pocket gun should be something you can shoot well with one hand, not marginally with two, IMO. People seem to imagine that they'll get into Weaver stance in a defensive situation, and shoot like they're at a target range. I think that's wishful thinking that can get you killed.