The Rampage is a good driver, but they tend to be inconsistent from disc to disc. I'd say the same thing about the Cannon. Very fast, usually fairly overstable. However, sometimes you'll find a Rampage or Cannon that is way flippy.
A good Rampage is something like a Boss or Nuke.
Rampage is a big time distance disc if you have the arm to get it turned over a little.
For $2 a disc you can't go wrong. Even if you decide to sell them off later you'll make a good profit.