Gigaworks t20 for cab?

hey, i am nearing the end of my custom vewlix cab and i am having trouble deciding on what to use for the sound side of things,
first off i was gonna use my uncles yamaha sound bar but that was too tall, then i thought something by logitech in 5.1 form but would be concerned that the sub would make the xbox jump the discs??? then i thought car speakers and an amp (could be expensive, but now i am considering a pair or possibly 4 of the creative gigaworks t20 pc speakers hidden behind speaker cloth.
Does anyone have any experience of these speakers and an opinion on how they would fare in a cabinet design?
cheers.