I was in the same boat when I was deciding between Pro and Premium.
The three biggest things the Premium offers that I think really do make a huge difference:
VUK on the Mode Start - I know people say they've added some felt or made minor adjustments to their pro to make it so the ball doesn't release into the slings or in a dangerous drain situation, but I'm not about making those adjustments. The VUK makes that shot so much more predictable and fair.
Kickback - there's not much to be said. If you've played a game with kickback, you know how awesome it is. If they add a software save in the next update, this feature will be more a little less of a selling point, however it does put the ball into play in a different way than a plunge. One negative! Even though the kickback stays lit for a few seconds in case the ball kicksback weird, there is still the chance that the kickback will mess up and not plunge the ball all the way and still result in a left outlane drain. It's only happened to me a few times in all my games, but it does happen.
Full LED - Wireforms aside, this is the cosmetic feature that blows me away more than anything else. You have to see it to really appreciate it. It's a cosmetic upgrade (whereas VUK and kickback are gameplay), but it's one of the coolest and flashiest things ever.
That said, I think the Pro is a fair option on this game. The major gameplay differences (VUK and kickback) are not as bad as something like missing a lower playfield or lacking modes, so if you opt for a Pro, you won't feel cheated.
Also, prices have already been argued, but I would go with a Premium and save $1000 if you're looking at going the Premium/LE route.