Quoted from CrazyLevi:Pro, all the way.
Why spend $1,000 more for a clunkier left ramp, all sorts of crap covering the playfield and obstructing your vision, the magna-slings (cute idea but I do not like them), and the "side to side Slimer" which really isn't very impressive or needed.
The GB Pro is another one from Stern where I really don't see the allure of the more expensive versions. I've played tons of games on both and all things considered it would be an easy decision for me.
So have I and then I bought a premium.