i really like sand... it's much cleaner than gravel because dirt doesn't fall between it... so it either makes it's way to your filter or you can siphon it off.
it does require a LOT of washing though before you it in...
any substrate will make your water cloudy if it's been in the tank a while and you stir it up... try stirring your gravel!
i might just use sand in the tank i am setting up too...was gonna use gravel....but sand is sounding better every minute, lol....just hope my fish show their colors good with having light substrate....i plan on having a dwarf gourami, german rams and cardinal tetras.