I have the 1.01 and I'm trying to trade down one spot to take Spiller there. If I can't, I'll still pick Spiller over Mathews. (I like Dez's skill, but I'm worried about any player that sits out a whole year--he slipped pretty far and I don't think a wide receiver taken #24 overall warrants #1 FF talk.)
I've noticed a lot of posters on this site going bananas over Mathews's situation--I think Mathews has the look of a decent NFL RB and he definitely landed in a situation that warrants consideration at the #1 overall spot, but he doesn't jump off the television screen. His top-end speed looks too slow on film. (I know he ran a 4.59 or something at the combine but he looks much slower in pads.) He has good moves but not great, he doesn't seem terribly difficult to bring down (even for those MAC kids). He just doesn't have that pop, even on his highlight films. His numbers look good, his FootballOutsiders rating is very good, his vision looks great, but he just doesn't have the look of a #1 overall dynasty pick.
Spiller looks special to me. He has that pop--it's more than just his speed. He accelerates and separates like very few prospects before him. In everything I watch, his vision looks very good--he hops outside a little too much, but not as much as folks have been saying the last few days. His abilities to run between the tackles and break initial tackles are greatly underrated on this board, too. It's not hard to find video of him moving piles, being very difficult to bring down, and maintaining his balance while being drilled by linebackers. He's also made some highlight catches and has good hands. And he played in a conference that just put 31 players into the NFL--the MAC had 5 draft picks. When you watched Spiller last year, he was out-quicking, juking, running away from NFL-quick d-backs and was bouncing off NFL talent linebackers.
I'll select Spiller even in Buffalo. Mathews will probably have a better rookie season, but in dynasty "good situation" should play a distant second fiddle to talent.