Colo - that's an option I'll try to stay away from as long as it is humanly possible. All of my experiences with colo hardware caused a lifetime of pain so that I'm happy to be paying SL a premium for their outstanding services (I'm a huge fan of Softlayer as you have probably guessed).

Re: Rackspace and other providers – based on my real-life practical experience with a few of the largest providers in the States, SL quality of services and their provisioning speed are miles away from competitors could offer. So it was a no-brainer to go with SL and I'm happy we did.