If they won't answer pre-sales questions like yours, how will they treat after you parted with the money?
As to RAID 0 it's a gamer thing. It's certainly less safe than one drive and yes, you need 2 to make a RAID 0 array.
More at http://reviews.cnet.com/4520-6029_7-5884226-1.html
I recommend the drives Gateway puts in the machine. Otherwise there will be finger pointing when it fails.
Planning on buying a P-7805u FX in the near future. It supports RAID 0. I have two questions:
1. Is buying another hard drive to create RAID 0 worth it?
2. If so, what hard drive would you recommend?