I'd probably buy a Neo Geo home system before buying a 360, Wii or PS3.
I was going to get an AES or MVS, but instead bought the ps2 releases of the games I wanted. Metal Slug Anthology pwns!!! It sure beats the the neogeo carts pricewise, haha. There is also an official aes controller for ps2 that is super awesome. My local import shop has the mai version in stock
http://neogeo.exar.jp/
Too bad,MSA for the ps2 suffers from controller lag up through MS 1-3 etc.
The most advantage i see in that is it has,MS6 wich was only on the atomiswave for the arcades.
As for beating it prices please it didn't cost me a fortune to get MS 1-5 on mvs.
It only hurts though getting it on AES of corse.
Kind of sad realy snkp got it right for other the collections...but can't emulate msa right for the ps2