I read back my post this morning and it sounds very anti-power conditioner. It's not ment to be - what I mean is if you want to use one because it lights up your rack, and provides and easy rack-mountable set of sockets for you to plug in all your great then it's great.
If you want to use one for the conveniance, then I think you should - but I would never say you NEEDED one as if they were essential.