A while back I bought a Mad Catz Round 2 Tournament Edition Fightstick and I've been playing the hell out of it. I like it a lot and I'd like to preserve its condition for as long as possible while actively using it. Which materials and chemicals should I use to keep it free from dust, smudges and scratches?
First off, always check the manual or with the manufacturer before you clean a device - you don't want to void your warranty or ruin anything that's particularly special about the device.
That said, I would suggest a hard surface cleaner (ie, Pledge for Electronics or similar) or a mild glass cleaner (ie, like what you'd buy to clean eyewear) along with a microfiber cloth. You want to spray the cleaner on the cloth, and not on the device, to avoid getting the cleaner into the device.
Avoid anything that contains ammonia or acetone, or anything not really designed for hard surfaces - (ie, bathroom cleaner, bleach, dish soap, etc) as these are not really going to be appropriate. Using paper towels or tissues is just going to leave lint behind.