Right now the poll stands at 32-3 in favor of looks over heft, with 6 who "don't care". I'm one of the three that voted for heft. But the poll is a little misleading because everything has to be within reason. So if a hefty metal model is only
slightly less detailed than it's plastic counterpart, I go for the metal.
A good comparison might be between one of those older Soviet-made models and a Dragon model. Hmm, never mind, because the more I think about it the more unsure I am that I'd get the Dragon. Never mind.
Hefty Soviet-made
Lightweight Dragon-made
(Get both!)