HELP: Need to buy 2 DDR metal dance pads .... need information

[unclet]

Ok, these DDR pads are out of my realm of knowledge ...... so I have questions.   I need to two of these metal pads to allow them to be connected with the arcade cabinet PC so my kids can dance away.   I also would like it to be able to connect to the Xbox in case there are some Stepmania-type games available for them as well.

Metal pads are selling on Ebay for about $100 each or buying a pair of pads sell for about $150.   

1) Are the Ebay metal pads good metals pads?   If not, where else should I be looking to purchase these things (ie: searching for DDR dance metal pad in Google returns way to many places to buy from ..... need some help here)

2) Did anyone buy a pair which they are happy with?   What kind and who did you buy from?

3) Do I have to worry about getting the "right kind" of metal pad so I can hook this up to my arcade cabinet PC? 

4) Do I need to make sure that pressing two steps (ie: buttons) at the same time actually registers on the PC correctly (if so how)?   

5) From Ebay I noticed all the pads usually have 2 corners which are empty (ie: no images)?  Are there some games which require all four "corners" to be stepped on during the game.  IF so, then I would like to get those type pads  ... since if I am going to buy two of these things, then I would like the pads to have everything which people would want on them.

6) What are some things I should think about before purhcasing?

[sc1103]

I bought a stainless steel pad off eBay-one thing I wish I had checked for however was if the panels are offset from the rest of the platform-either raised or sunk somehow.  Now when I play with mine I can't tell if I'm off the squares until it's too late.  As I wear it out though I've noticed the sensitivity has gone up and it's easier to have it respond to slightly off presses. 
Also the pad should have a USB connector if it's PC compatible, and since we're talking about pads they should be able to naturally handle two presses.  If you buy PS2/Xbox pads and a converter, make sure the converter can handle 2 keypresses, or has a switchable "Dance Mode" that allows simultaneous keypresses. 

Highest quality pads are Cobalt Flux or RedOctane but with high quality comes an expensive tag.  The only games with corners that I can think of is the one Paige used to play-Pump It Up I believe? but that also required a center square, and only Cobalt Flux pads have that as well if I remember.  Many pads have a control box that allows switching between PS2/XBOX/PC so I'd look for that. 

The bottom two that are missing are the equivalent of O and Triangle in PS2, at least on mine, so you can get away without them by using select, but they are nice to have.

[Dreamwriter]

I love my CobaltFlux the best - top notch construction, the things are bulletproof.  But as was mentioned, they carry a high price - $300 a pad, with a little discount for buying two, and a hefty shipping cost.  It comes setup for the PS2, so to make it work on your PC and Xbox would require an adapter (any normal PS2 to USB/Xbox adapter will work).

[unclet]

Yeah, I think the Cobalt pricing is too high for me ..... the RedOctane (Afterburner) metal pad is $199 plus shipping and is ready for Xbox and PC already.