I've had Dish for about 16 or so months. Probably in a few days I will be switching to Direct TV for a few reasons:
1) Our main reason...Our 508 (60 hour PVR) has died 3 times in 12 months. Each time they were willing to replace the unit under our "Digital Home" plan, but we are getting sick of the HD failing and only getting refurb units back.
2) TIVO is much better than normal PVR. If you dont know the differences, a PVR (Personal Video Recorder) acts like a digital VCR. Dish network's version of a PVR is just that a digital VCR. If you want to record something, it has to be on that channel and you can't change it. You can only record 1 thing at a time. Plus it is based on time, so if a show gets moved then you end up recording an hour of crap you don't want. Dish is working on the problem, but who knows when they will be moving to a more Name based recording like Tivo.
3)Cost is about the same for both units. You get about the same number of channels for the same price. Dish offers stuff at a lower up front cost, but now they charge money per month just to have their PVR. So it's a no brainer. Pay for the features of Tivo or pay for a digital VCR.
4) DirectTV's TIVO unit has dual recievers. So you can record conflicting things or record something and watch regular TV while it's recording. Very nice in my opinion.
BTW, my monthly bill for 3 recievers on the top 100 (second level of programming at dish) is approx $56 every month. Of course I was grandfathered in before they started charging for PVR access so it would be more if you had the same setup (1 508 and 2 301s)