The way I understand their pricing (.05/hr, .10/hr, .15/hr based on minutes jobs get pulled off queue), I'm essentially paying 3x more for priority queuing that I can bypass by setting the INTERVAL=3 in Resque. Hm. This an expensive way to set a variable.

IronWorker is billed by the second so if an image takes 5 seconds to process, you only get billed for 5 seconds of the hour. No need to deal with auto-scaling heroku workers to keep your costs down.

And priority on IronWorker has a much different meaning than setting it on your own private Resque instance so comparing that based on price isn't really a fair comparison.