Subject says it all. I have both systems. Arcade stick for the 360, but it's a 6-button one for Capcom games. Don't know if that matters, I think the button layout for DoA games is different. I just don't want to buy one version and find out that I should have bought the other.

@DustoMan: The DOA button layout is just the same. I actually posted a topic about the official DOA5 stick. I think there will be more people playing on the 360 in the long run as DOA 3 and 4 as well as DOA Ultimate were all on Xbox only platforms. So, greater chance of a bigger online community. Honestly you don't even really need a stick for DOA. Its easy enough to play with a pad but the Capcom stick should serve you well enough. You might have to remap the buttons to your liking but otherwise seems totally doable.