Not having to manage tapes is well worth the extra money. It's hard to convince someone of this without doing it, but it's true.

A caveat about DSS control, and it being better than the VCR: I have the TiVo controlling a DSS receiver (a Sony SAT-A1) via the serial control and it freaks out the receiver unfortunately often and it stops changing the channel. I'd do some research first and see if anyone has any similar problems with your receiver. The other option is to buy a DSS-TiVo combo unit, but these don't have a tuner to record broadcast TV, which is a glaring omission, as a lot of what I want to tape is on UPN or WB, which don't have DirecTV channels even if you do get your other local channels. There is also, as of this writing, I believe, no ethernet hack for the combo units.