On a limited budget I would opt for QS4s and get a different sub. This would be imo a much better match for your size room. From what I have read the QS8s are the better speaker but for your room size and budget I would opt for the 4s.

Not to say your radio shack sub doesn't please your ears but it is not in the same league as the ones I linked to.

Rick


"A fear of weapons is a sign of retarded sexual and emotional maturity." Sigmund Freud