I like 'em all but am especially partial to the Original Series ("TOS").

I've done several detailed polystyrene models of the Enterprise, Klingons and others - I'll post some pics here eventually. Some are even fiber-optically lit.

I also have a thriving collection of models, figures, books and other memorabilia covering not only the various Star Trek incarnations but Sci-Fi in general.

I'll be adding my own and tips and perspective on modeling specific Federation (and alien) ships like the Cardassian Galor, DS9's Defiant and the mind boggling fiber-optic DS9 station (a supreme challenge).

Keep phasers armed and ready.