Tivo Life extension

I'm contemplating an offer that will get my make my TiVo (a Premier) a "life time of the device" account. Since hard drives are the most likely point of failure, I'm contemplating what I should do (now) to ensure that I can recover from a hard drive failure (later, when it inevitably happens). I'm a competent hardware guy in general, and did a number of "upgrades" with my old Sony-T60 + DirectTv.



Thanks