I gotta say, this one is a little iffy. These rebates have the same promotion and "mail by" dates. Previous dual rebates from Staples/Maxtor have had different "mail by" dates. I've gotten dual rebates before on the 80 gig 8 meg cache drive as well as a 60 gig 2 meg cache drive from Staples (sending a copy of the UPC to the Staples rebate).
With that said, it's worth a try.
Not to mention that if you go to Ebates first, you get an extra 2% back, and you can manually enter that $20 off $100 coupon code (don't you just have that COUPONCRAZE going?!)...and if you use a credit card registered with UPromise, well, there's a little more back in your pocket.
Good luck!
Joe