The plus has a thicker card stock. Technically, there will be three different versions of Prestige - the regular (non-foil set), Prestige Premium and Prestige plus. There's no cross overs.
Looking at the cards I've seen posted, a lot of people aren't listing if the cards are 'plus' or 'premium'. It's also hard to tell from pics what cards are the thicker stock ones. What I've noticed those if the premium tend to have a more refractory type foil to them, whether as the plus cards tend to be more mat foil. Has any one else got any of these cards in hand to confirm my observations?
From what I have read, there are only parallels for the Premium base cards which is printed on a thicker stock. The regular Prestige base is thin like the old cards and has no parallels. So you can trim down that list back to just one set of rainbow.
Just following on from this, I've seen that each set does have the same number of parallels, ie there is a gold /10 in prestige, prestige plus and prestige premium. I have actually managed to track down about half of the list so far, but just thought I'd confirm that the original list I did post is infact legit so I am chasing the 24 card set!