Trim. I'm a hirsute dude, so any shorter than a trim and it would look like I have a -very- weird bald spot.
In general, shaving it all is going to look weird on any guy who's not a serious bodybuilder. General advice I've found, and follow as needed, is trim everything to a #3, use a #1 or #2 closer in, and if you really want to put in the work, clean shave only the shaft. Otherwise, just use the trimmer bare.