Keep in mind if you buy a new TiVo and install your old hard drive from a broken TiVo, your shows will not be accessible. TiVo marks every show with the serial number of the unit so if you swap the drive the shows you recorded will be seen but won’t play.My Bolt is going on five years now with no issues yet. It has a one terabyte drive and I added external cooling shortly after purchase which I think helps add longevity. I purchased a Toshiba replacement drive about eight months ago just in case! Love my TiVo… hopefully it will continue to be trouble free.