it's been my experience that that the quality of the build is more important than the number of spokes or the depth of the rim. one of my wheelsets is 28h low flange hubs laced 3 cross to low profile rims. i had them handbuilt at the LBS by someone whom i had heard good things about. granted i'm not all that heavy (140lbs) but these wheels have held up very well to street riding, potholes and all.
contrast that to a set of 36h (probably) machine-built deep v's i got on ebay that were constantly going out of true.