The Stillen module is a generic tune, as is the Bully Dog. Between those two, I would wait on the BD, as it is cheaper.
Between the Stillen module and UpRev, I would go with the UpRev for a few more dollars. With the UpRev, at least you are getting a custom tune and the WOT restriction is removed. Plus, as you add other mods, you can get retuned.
