Regarding the 511 glitches, I've seen them too. Using the pause, rewind feature, is really erratic now: I jumped back a half hour recently, when I was trying to go back 2 minutes or so. Really peculiar; that new software is buggier than anything I've ever seen from Dish Network.
The above being said, if you just start a show and let it roll, no problems. The pause, record, rewind functions need work. L449 worked just fine, by the way.
Fitzie