I've done some benchmarking of softlayer cloudlayer and their "SAN" back cloud servers have about the worst IO performance of any provider. Even the largest 16 and 32GB instances performed extremely poorly. EC2 EBS is a much better performing storage platform. Stay away from cloudlayer if you have anything even remotely IO intensive.

http://blog.cloudharmony.com/2010/06/disk-io-benchmarking-in...