I have been playing the pro that we have on route at a local bar quite a bit. I set up a friends LE Friday and played a few games. Really didn't see much difference in game play from the pro. The Borg jackpot style shots at the right flipper are really cool. The ramp lock is neat because of how fast the 2nd ball pops out when mummy multiball starts. There was also some kind of crazy strobe light thing going on during Powerslave that I did not notice on the pro.
I definitely think the LE is more fun to play, but the pro plays just fine. I am getting a premium but would say the best bang for the buck is the pro. The pro art is closest to classic Iron Maiden too so that is a win.
I have been holding back on saying this but I think \m/ might be the most fun Stern ever.