At BestBuy, I had a good look at the new tablets and was very impressed. First, I played with the NotePro 12.2 and loved it; it was not in any way too big. In fact, the size was a huge plus. In using multi-window, the 4 separate windows is nice and you can see that it's really meant for a large screen. The 12 was very responsive and felt sturdy. Also, for it's size, it felt pretty light. Even though the new ui is interesting, I will use Nova. Too bad it's not cheaper.
As for the 8.4, the screen is fantastic. It will make a great indoor ereader. To date, I have never seen a better screen. Also, with it being a bit narrower than the mini, it feels better in the hand. I saw no lag (on any of them). However, I love the s pen so no tab pros for me.
Though all are nice, they are on the expensive side.
The materials are typical Samsung; not bad, but not high end (my Note 3 is the same). For me, not an issue; for others, maybe.
Most likely, I'm going to get the 12. Unfortunately, it won't be for a few months.