I think you got a great deal!! When I got my 622 when they first came out, I paid $299 with no rebate to lease. They dropped the price 2.5 months after I leased mine.
I've gotten tons of use from it, and no downside for me (other than the price--that's a lot for me). I have often recorded 3 shows and watched a previously-recorded program at the same time. I rarely use PIP. I just record and start watching before the program is finished and often catch up to "live" recording.
I use mine in single mode in a large room, so I have both remotes set to use in the same room (yep, I know, really lazy!).
I haven't missed any recordings, but for shows following sporting events, the 622 will automatically record an extra 60 minutes, but I will set recordings even after that. Some football games even run 1.5 hours after the scheduled end times.
I hope you enjoy yours as much as I do mine!