Alabama is not a good yardstick to use to measure Arkansas ability. Alabama beat Hawaii by 5, and Vanderbilt by 3 (in the last minute). Alabama is just as bad as Arkansas.
But as Wyatt pointed out - OOC is a red herring. YOu have to compare the entire Schedule.
Auburn plays LSU, Florida, Georgia -- as pointed out, All top 10. LSU only Loss is to Auburn, and this will probably be thier only loss. Florida is undefeated, and only losses likely are to LSU and Aurburn. Georgia is undefeated and may lose to Florida, Auburn and possibly Tennessee.
USC plays - ND, Nebraska, Oregon, California -- All top 25 but, ND has already been totally exposed, Nebraska is o.k. but not great (they will lose at least 2 more games), Oregon honestly lost to Oklahoma and California got spanked by a Tennessee team that is showing itself to be a good team but not great.
OK. USC schedule is the toughest, entire or otherwise.