I am unsure which DVR receiver I should buy in upgrading from my existing H20 receiver. I am unsure about the differences between the HR20, HR21, HR22. DTV offered me a free DVR upgrade, but they will not ship it to me for self-installation. They said they HAVE to ship it to an installer, since it's not replacing the same model as I presently have. I found it curious that they'd rather pay an installer than allow me to install, which I've done in the past. I have the required SWM 5LNB & power inserter for my SlimLine. Suggesting to them that I may switch to DISH didn't seem to do any good. Also, I bought the RF-capable remote for my H20 receiver, and I wonder which DVR's it will control.