Im planning on purchasing a system for my X5. This is what im thinking about getting; A pair of 10w6v2's, the speakers are going be Focal or Boston, if its Focal im going go with the Focal K2P's in the front and polyglass in the rear. I'll be powering the subs with a one 500/1 amp and the speakers with (2) 300/2 amp's. My question is, should I get a 450/4 for the speakers and get (2) 500/1's for my subs or keep the two 300/2's and get 2 500/1's for the subs?? Any suggestions would be great.