I know this may not be an issues for some, but my UTV and TIVO change channels around 2-3 seconds, I love that and hated waiting the 5+ seconds my old DP acted. I hope Dish improves the performace with the 721 in the future.
Both connections need to be from your Dish or Multi Dish Switch. You can not have your Dish on 1 input and cable TV on the other input. The 721 like all other Dish Network receiviers are MPEG receivers not NTSC receivers.the 721 run ok if one of the inputs is from your cable company, or do both have to be satellite?