I was at Disney these past 3 days, stayed on site, and fully utilized the magic bands. Now, I will admit, it was cool and convenient to have everything in one place. But, I did have some complaints. First I did park hop, every day I was there, and was really peeved that I couldn't schedule one at a different park, even if it was 2 at Epcot and 1 at Magic Kingdom, had to do all three at one park and guess what times I would be at each park. Also, when I did the FPP online, it restricted me to 1 major ride and 2 smaller ones, but when I did it in the park for same day it gave me no restrictions, and in the park was very quick and simple. I found a FPP line that luckily didn't have a long line, but it amazed me how long each guest is there figuring out their stuff, it took me about 2 minutes tops. And the lines out the FPP were a bit ridiculous, but that is because guests are CLUELESS. I don't know how many people I watched try to scan their bands by holding the wrong park of the band to the thing, or people put their finger on the scanner for some unknown reason. But once you get into the actual line it's super quick, but I can't imagine the frustration these attraction hosts have to experience on a daily basis because of these people. And I saw a ton of people just jump into the fastpass line once in the middle, just to hold everything up once they got to the second scanner. So yeah, I definitely prefer the old Fastpass system since I could easily get more than 3 rides with it, but this system isn't as terrible as a lot of people here are making it out to be.
But yeah my major complain was having restrictions as a guest who paid for a hotel room but having no restrictions as a guest who was just in the park.