I didn't ride Summit Plummet. My DD was 6 and BARELY 48" when we went, and she decided SP was too much for her, so we hit Slush Gusher (I think that's the name of the one next to SP) while DS8 went on SP. He was the 3rd rider of the day!

He said that it was awesome and he wished he could have ridden again, but the line was already getting long by our 2nd trip up the lift, so we opted for another trip down SG instead.
I don't know what the angle of the drop is, but you're right - it IS pretty steep! Now, when I first saw it, I didn't understand what the slide did! I saw the part that looked like a ski jump, but I didn't see the rest of the slide that passed under it! I didn't know what it was all about! At any rate, I WOULD have ridden had DD been up for the challenge (she did later say she regretted not going, but it wasn't worth waiting in that line again).

The only negatives on SP and SG are that the water really slaps you as you go down. We all had red marks on our backs after our 2 trips down the hill, but I'm the only one who seemed to notice. I must be getting old.
Not sure on the beer, though. I don't remember seeing beer carts, but I wasn't looking for them either (no, it was a few days later in Epcot that my margarita craving was in full gear...

).