give us a rough budget, something more specific than 'nothing really expensive' cus that can mean diff things to some people.. i might spend $1000+ on the HU alone, while others will use that for their whole system.. nah'mean?

most quality head units have decent sq but nothing to rave about. you'd notice and gain a lot more 'clear & depth' with splits, amps & subs along with tuning & installation. what else do you have in the car atm?

what tuning features do you want? basic bass/mid/treble eq'ing fine with you? or do you want time-alignment/correction & comprehensive parametric x-overs?

all in all id probably look at alpine or eclipse head units.