The latest model for RCA is the DS5451. For Hughes, I believe it is the D4632. I know the RCA is only a 3rd generation receiver, not sure about the Hughes.
I don't own the Pronto, so cannot comment on its use.
I have heard that both Dish and DirecTV are working on digital recording and are targeting the end of the year. I believe that RCA is also looking into working with ReplayTV on something. I think there will also be additional charges for use of the services as well. Don't really have much more info than that.

Oh, one other thing which may or may not influence your decision. Currently the customer service from DirecTV is really bad in that it's extremely difficult to get a rep on the phone (unless you're a new subscriber, somehow those calls get through just fine). Don't know if it's because of all the changes they are going through (converting Primestar, absorbing USSB and restructuring their package offerings, etc.). Hopefully it will get better in the future, but since I haven't had to deal with them very much, I'm ok with it for now.