I had to return an IBM drive (through the retailer though) with no problems. However, in returning computer products, I've always found that playing dumb is a good tactic. If you try to throw around terms like RAID 0 and DMA to even a "support technician", chances are good they're going to jump to the conclusion that you broke it by messing around with it. If you play dumb and just say "I dunno, it just kinda died on me. Scandisk says so.", you might have better luck.
Oh, and keep your temper. The angrier you get at the person on the other side of the line the more resistance they'll put up.
-Jason