If it is something you would like to have, then it is a good idea.

I built my arcade machine with an Xbox, though mine is pretty much a standard cab. I wanted to use an Xbox so I could play modern fighters on it, as well as other various arcade control friendly console games, and also us MAME.
It has worked out excellently for me.
If for whatever reason I wish to use a different controller, I have an adapter so that I can just plug it into one of the memory ports.
With a PS2, there is a lot of games that would play great on an arcade cabinet. It has a great set of light gun games, as well as a vast number of fighters. I have actually thought about putting one into my cabinet, and installing a switch box.