Yes, amazon is 'overpriced' if what you're looking at is CPU or disk speed (which is not a bad metric, really). Where amazon shines is the amount of programmatic interaction you can do with it - have build scripts kick off an EC2 instance to run tests, send reports, shut it down. Programmatically bring up more instances during peak times, spin them down at night, etc. AFAICT, Linode doesn't offer that, and they proba…
While perhaps not entirely as mature and full featured as AWS's offering, Linode does offer an api with which you can script creation/initialization of test servers.
See https://www.linode.com/api/linode
They also offer something called StackScript, that to me looks like some kind of configuration management script. https://www.linode.com/stackscripts/