I'm warming up to mixed group comp myself. I used to be dead set against it. ATM i have a lot of 85s i gained via RaF and can do any comp I want. I had an oddball of an extra warrior/DK/rog that i made a trio out of. I went to lazymacro forum and got some quick lazy macros for them. ATM the trio is the best DPS i have seen out of 85s. My rog is combat speced and was bursting on an 85 target dummy to 21k and does 13k sustained dps while questing, all 3 of them sya in the 10-13k range. My end goal is to have a team that can burn through heroics and has a great chance of getting silver challenge modes. SO whatever comp that ends up being, great!