My Amiko NanoHD gets the RTV mux (4000 H) on 87W fine with a 6 ft Fortec dish that has a BSC-621 on it. Quality is 65 to 70.
The A3 connected to the 8 ft dish has a quality of 85 on the same channel but that dish has Chaparral LNBs on it.
The Mini HD and a 7½ ft dish should be OK.
BTW, I'm located in central NC.