"The quick answer is there is no going back to V6 TiVo once you have moved to 360."
This is not strictly true.
We "upgraded" to Tv 360 and were rather disappointed as others have voiced similar concerns
Have posted on some other threads I can attest to YOU CAN GO BACK TO TIVO. I must point out though it took 3-4 months, many phone calls and a "call from GOD" ( tech level 2 ) to get this authorized
Had an engineer out the other day and he replaced our old TIVO box AND our V6 box that had been "upgraded" to TV 360 with 2 brand new V6 boxes both operating on TIVO so we are shot of TV 360 and are back on TIVO and are happy to have got rid of the "upgrade"