ok, way too much information, but anecdotally:
(note: not a doctor, and this will probably kill you)
pygeum - definitely helps
zinc/selenium - probably helps (though probably depends on how much you're getting from your normal diet)
l-arginine - maybe, though the recommended doses for full effect are quite high, can boost NO at reasonable doses though (as can VitC+garlic)
grape seed extract - sort of, seems to act as a diuretic, so lots of watery volume (also, being very well hydrated helps in general)
soy lechathin - possibly, seems to be the most recommended thing but makes me feel like shit
nettle - possibly, seems to help flow
maca - doesn't help, but great for libido