Well, since I don't have HIDs, I honestly cannot answer your question. However that may be, what are you looking for? Just sound? Performance? Or both?
I personally was looking into Conforti's intake. It's just under $360 w/free shipping from M3Motorwerks
In combination with a chip
, Hp gains are noticable at 14Hp and 11lbft. Not to shabby.