The only recent downtime was an instance a few months back where I fat-fingered an iptables config. A tech was on the pulling up the console and cleaning up my mess while I was still typing out a support ticket.
Just make sure the person signing the hosting contract actually reads it, also. You might be surprised to find what they try to bury in there.
It's worth noting that they bought out their lower-priced competition at ServerBeach.
Not sure what/who you consider "great" then. Rackspace has been stellar for us–always available on the phone; answering tickets fast; alerting me when there are problems.
I've never had a bad cs experience with Rackspace. (I've got 6 servers with them)
They're just overworked like most NOC guys.
Anyway, I've never had any reason to complain about Rackspace service. Now, I'm not saying the service is a good value (you definitely pay a premium), but it's been solid for me.