I got an Extreme Bulk pack on Ebay for $109 + S/H ($30....it's heavy). There's 36 sq feet in a bulk pack. If you're gonna do it, get a DURABLE roller. I'm a FIRM believer in using D'mat where ever possible. Here are some picks from my Monte Carlo D'mat install:

http://icd.ics.purdue.edu/~berk/pictures/Monte_Carlo/

PS: got the rear door D'matted tonight