Wow, didn't expect this thread to be going still.
So having discovered my old avatar is not in fact virtual worm food and successfully recovered him and his 8-year-old transaction limit, I've done my own legwork, which maybe others will find helpful.
in general, I've found male clothes don't require nearly as much precision fit to look good as female clothes. Alpha cuts are the way to go, and in fact I've found that when given options between a piece of clothing that has versions designed to fit a specific a body, a fitmesh, or multiple sized options designed for classic avatars, I actually prefer to go with the sized classic option and alpha the pokethrough out for a more realistic look. Otherwise, even the specially designed options look bulky, as if the cloth is floating rather than resting on the skin.
As for bodies:
Adam - In combination with the head, this is a really cost-efficient choice and is the only combination I've yet encountered that has zero neck seam under any lighting condition. Support-wise, it's a bit of a problem with certain clothing styles, especially open jackets that have no undershirt. The reason is Adam has larger lats than any of the other bodies (but consequently looks better for a muscular build, imo), but the alpha cuts for the sides of the torso don't go down far enough to be able to hide the sides of the body rather than an entire front ring section.
Gianni - People were right in that this is probably the most solid choice. Imo the physique is not quite as natural, but I've yet to run into any issues. I'm running with Catwa's Daniel right now, which is a super expensive setup that requires buying a whole bunch of extras and even with a fully matched head, doesn't quite eliminate a neck seam.
For me, the perfect mesh body would be adam's shape and out-of-box skin options and gianni's alpha cuts and hud design.
Here's how I ended up:
This is with Gianni with a shirt designed for classic. With Adam, his lats would have been poking out of the shirt mesh under the arms with no way of hiding it without ripping out the chest. I did come up with a solution of sticking a pair of shoulder-holstered berettas underneath to hide the popout, but that's kind of tacky and blew complexity up.
And for good measure, what he looked like when I first dug him up. 2008 baby. Look at dem' bullets!