Buy the TF Pro for sure and this coming from someone who owns the LE.
The LE's are a waste of money, the poorly implemented toys on the playfield make the overall gameplay worse on the machine as opposed to better. The ironhide mini PF is a chore to play and pointless at best.
I do like the Starscream toy but only wish it was implemented more often and used it a much better fashion.
TF as a game is ok, it's nothing spectacular but it's not the worst game out there, I've been finding myself playing mine again more lately since the most recent code update as it has made the wizard mode a more attainable goal.
But for the money I'd say your are better off buying any number of other Sterns (Tron, ACDC, TSPP, LOTR, IM, etc, etc) they all make better playing games and are priced similarly in the Pro category.