I have my cable through Comcast and am currently renting their Dual Tuner DVR box monthly.

I am about to upgrade to HD tomorrow and want to know if I should continue to use their boxes or go get something like a Tivo. Fios is not offered in my area yet and I live in a Condo so DirectTV is not an option either.

Get a refurb Tivo HD for $179 at tivo.com. If you get 3-year subscription for service, the monthly cost will be about the same as for the Comcast HD DVR over those 3 years. You will lose OnDemand, however, you will get a much better box for the money.