I've never heard the creative ep-630...
but I've had quite a bit of time with the super.fi 3's. and I must say I have not enjoyed them at all. I did not find them to have much clarity...it seemed muddled alot by the bass. Maybe I've been putting them in wrong after my many attempts..or I'm just not an IEM person.
@Steve72: I think you probably did choose the lesser of 2 evils. If you're happy with the buy... just enjoy it for the time being. Don't be in a rush to upgrade, try to wait it out maybe hit up a mini-meet or try out some phones between $50-$150 that your friends might buy. If both these options fall through...read up here on head-fi+save up a bit of cash, and you could maybe hitup the for sale forum and if you find the improvement to not be audibly there enough to justify the price, sell it back to other head-fi members. Coould be a great way to try out entry level grados/senns/whatnot.
a few of the statements here have been pretty strongly in favor of one can or another... what one member likes, might not be what you like. so don't rush into a buy that you'll regret alot.