Let me take a stab at this from a couple different angles.

The pre/pro side of the equation is HK635 vs Outlaw 970. I would suspect that the 970 will come out getter in this deal - the design's a year or so newer and it's a true pre/pro (so there's no amps under the hood).

The Rotel 1075 is a 5x120W amp, while the Outlaw 7075 is a 7x75W amp. The combo price on the 970/7075 at the moment is pretty potent ($1100 for the pair), and the extra two channels would let you move up to 7.1 later if you wanted to. On the other hand, if the deal on the 1075 is good enough that might change the equation.