I won't say that one is better than the other, they have some differences in programming, and each has their cheerleaders and detractors.
We have Dish, and we have been relatively happy with it.
With Dish, you buy/lease your equipment from Dish.
With DirectTV you have a wider choice of equipment vendors.
Dish offers DVR units, DirectTV offers Tivo.
Dish seems to have a better selection of HD programming, plus a number of educational channels that DirectTV doesn't have.
Some premium sports packages are only available on DirectTV.
We made up a spreadsheet with all the channel offerings and pricing tiers for both vendors, and selected Dish as having more of the channels that we were interested in.
