I'd like to buy my wife a DDR setup for ps1 for xmas. What are the issues with the pads? Is it worth spending a few more bucks and getting a hard plastic one like this:

http://cgi.ebay.com/ws/eBayISAPI.dll...&category=4303

Is this a two player simultaneous game? Would I need or want a second pad? Will any of the pads have problems on a concrete floor? My wife loves dance aerobics and this is also likely a game genre she can whoop my ass in, so it looks like a solid gift.