I used to work for iServer (later bought by Verio; in full-disclosure, I'm now a contractor for Verio). I remember one time the city had shifted their output by 90° (or something like that...this was years ago).

Our datacenter UPS was tied right into the 3-phase output and didn't recognize that the power was still flowing from the city. The diesel engines fired up and started powering the datacenter (redundantly). When the gas ran out a few hours later, everything started shutting down. It was terrible. Hundreds of servers with 600-800+ days uptime all went down and stayed down for hours. We were shuttling people from the office down to the datacenter to fsck and bring machines back up. It was a long night and long next week issuing credits to customers who had lost data.

Today I've got servers with Verio, Bluehost, and LayeredTech. They've all been great for the most part, but none of them have been near perfect. I know that most hosting companies I've worked for or dealt with put uptime near the top of their list of priorities because they know it's an easily measured number people bank on. I'm sure RS will get their act together and be as solid as they've typically been in the past.