I had Dish Network's full "Everything Pak" but when D* added all those HD channels, I scaled back my Dish programming to their smallest package and HD LiL's and OTA HD. I've been using DirecTV for all the mainstream hi def national and movie channels and after only two months, the hard drive is near full! The two services really compliment each other. Dish has a much better DVR with their 622 and a much better OTA tuner, but DirecTV has the best line-up for me.
As for SD, I really haven't done a super close comparison as I don't watch much SD content on either system, but would have to give a slight edge to DirecTV on national channels. However, we are in an extremely rural DMA, and our locals on D* are absolutely terrible. Worse than an mpeg movie on the net.
The premium movie channels in hi def, both in number as well as quality, are far better on Direc than Dish, especially the MPEG4 ones. Those are amazing, rivaling the HD I've seen on my C-band system (which is almost defunct now). They're doing a pretty good job right now and I hope D* doesn't start overcompressing channels to fit thenm on their satellites like E* has been doing.