We just bought a Premiere 4 (4 tuner with Lifetime and ext. warranty*) to replace our 2 year old Series 4 (2 tuner with Lifetime). (Going to be selling soon) I just wanted to say, the P4 has a significantly brighter video output (side by side to the S4) that I wasn't expecting to see. I'm not sure how this difference would translate on an LED screen, but on a 60" DLP screen it makes quite a difference. At first I thought it was just in the menus - but it's in live TV and recordings as well. Whether one likes it or not, is a YMMV - but it was something unexpected for sure! Just sayin' ... *We also bought the 3 year warranty on the P4 - only a 90 day manufacturer's warranty on a brand new Tivo box is scary. I've never had a Tivo break, but it sure indicates a lack of confidence and support for the hardware on the part of the company!