Thanks Uli. Could the choppy playback be connected to drive speed? (it certainly doesn't seem to matter that much in RedCineX)... I normally play off a G-raid FW800.
Currently we're using a G-Raid via esata.
Here is a test you need to do. Add a single red clip to a matching sequence in PPro. Make sure you have a clean system start and no other apps running. Open activity monitor. You should see 1-x number of processes called ImporterREDServer. Start playback in ppro so you can still see activity monitor. See if the ImporterREDServers are doing any work. They shouldn't be. If they are the rocket is not being used.