I bought a new tux at K&G Menswear years ago for $99 - I still take it on the cruises and it still looks absolutely fine.
As for the tuxes (and suits) of a different color - I have seen "suits" of many different colors worn by individuals who carry the color off in an exemplary manner.
What is most interesting is to see the nature of color as it applies to the different cultures of this world - particularly the women. The colorful patterns of the african nations; the saris (sp?) of those from the Indian subcontinent, etc.
To me, the more color, the better - it brightens the night.