If you want durability, a Japanese machine such as the Panasonic ES10 at $180 (amazon) is probably a better bet. That said, my three 5005s have been without major problems for 8-12 months (other than some media problems that ALL recorders will experience).
The 50xx series is probably the only major recorder that can do the Macrovision hack and that should take care of your protected content problem but not the jerky motion. The latter is probably due to prolong recording (be yond 1-2hrs) and/or heating problem.
Beware some 50xx MAY have problems after the any firmware update, especially the drive firmware update (there are two firmwares for each recorder; read up on it).