I have the X-530..I was considering taking everything out of the sub box, buying two 15" 8 ohm subs for $20 and running them in a 1cf sealed box at 8RMS to each.
okay, I just ordered a few things.... 8800GT (the new one which is better then the 8800GTS) Vista Ultimate 64-bit, a Logitech G25 steering wheel, Logitech G51 speakers, new motherboard, new CPU cooler, and a few extras... lets see how it runs soon enough, aye?