Exelion's Basic model includes an incredibly fast Xeon processor, 16 GB of RAM, RAID 1 storage and a gigabit port for $99 per month ($66 per month with 5 year commitment).
Compare that to Rackspace which I'm guessing would charge about $1 billion per month for the same thing although I haven't checked their prices lately. In all seriousness - Rackspace can't come close to their pricing.
Other than that, there are still some open questions - where are they located, how can we be sure they'll still be in business a year from now, or hey, what operating systems they support, etc.
Anyway, my point is exactly that you say "anyone who has evaluated Rackspace." The OP doesn't make claims one way or the other, and if I don't have my own claims I'm willing to evaluate using his service, there's no call to action (I can't believe I just used that phrase).
And he financed it with his bitcoin winnings, I guess.
Why or in what circumstances people should choose you over, for example, Rackspace or cloud vendors like EC2 might be a good place to start.