I've got Dish Network and am pretty satisfied with it, even though we temporarily lost the Viacom channels (which includes CBS and MTV) for a couple of days because of a fee dispute. But Dish made up for it by crediting us a few bucks off the following month's bill.
Not that much difference in programming between Dish and DirectTV, other than the above channels you mention. Pricing packages are about the same as well.
Whichever satellite provider you choose, be sure and get the digital video recorder package... greatest thing since canned beer!