what sort of deck Chriso?
My most recent system was built for SQ (apart from the sub lol), i had a pair of MTX TXC6.1 splits, run off a bridged TH684 (each Speaker was getting 280rms) these splits are bi-ampable, meaning you can amp the tweeters also. Make sure you get a good set of splits (mine are for same btw lol) and a well powered amp to run them.
Id still recommending getting a sub... a good quality one, in a box designed for nice, tight, resposive bass reproduction