I'd think twice about the Premiere. Consider this post:
which contains this statement:
The Premiere is a piece of crap, and a serious black mark on TiVo's history. If it's the only TiVo you've ever owned then I'm sorry. You picked the wrong generation to join the TiVolution. I've only had my Roamio for a couple days, but it is everything the Premiere should have been. It's fast and usable and actually capable of fulfilling TiVo's "one box" claim.
But you will have a lot of company.
Also, I think betting that Premieres (or any Tivo) will be immune to TA-related problems, including GC failure and S03, is a sucker bet. My guess is Tivo market penetration would be at least 50% higher if it weren't for the infernal TA.