I have been with 1&1 for over three years now and I have never seen our dedicated server go down. Their network is first-class and I have actually been able to get transfer rates of over 10MB/sec on our 100Mbps port.
I'm in the market for a colo host now because our current hardware is getting old and the CPU is really loaded down, but in my search I realized how many bad comments there are and how few good comments there are about hosts. Therefore, I just wanted to try and make the reviews more equitable before I leave this host (and possible get ripped off at my next one
I know that 1&1 rightfully so gets major flames about their support but we have used their dedicated servers for about a year also with nothing but 100% uptime and blazing speeds. Good luck finding a host on here that has not been hosed by someone, I've looked (and looked - and looked!) and am yet to find one