I had a good G+ experience the other day I wanted to share - shows the power of the refresh trick:
We got to the parks around 430pm, and needed to leave around 10pm. It was a typically busy day - headliners were all 45 min type lines or more. When we got there, the only rides with availability before 10pm were Star Tours, Buzz, Incredicoaster and Grizzly River, so my wife said we shouldn't buy G+. But I decided to do it anyways as kind of an experiment.
Grizzly was closed, and I knew it wouldn't reopen that late, so I knew if I booked it it would become multiple experience. I booked that right away while we ate dinner in DCA. Annoyingly it didn't become multiple experience until the 1 hr window ENDED (i was expecting it to convert as soon as the window started), but we were able to use that for Soarin, which we did around 615pm after eating dinner. After entering Soarin, I started refreshing, and managed to get BTMRR for 730pm, so we headed to DL. We did Star Tours standby, then rode BTMRR. doing refresh I managed to get HMH for 815pm, which was perfect - we shot the rifles to kill time. With refresh i could've gotten Millennium Falcon but we didn't want to walk all the way back there so we booked buzz, and then refreshed and got small world.
So despite basically no availability, we managed to use G+ 5 times (soarin via multiple experience, BTMRR, HMH, buzz, small world). I never saw Indy or Space mountain come up, but with refresh we pretty much could've gotten anything else (I saw guardians at one point but we wanted to do soarin, and saw all the DL rides except Indy and space at various points).
Now, we were a party of 2, and didn't have our kids with us. If we'd had our kids, I would not have bought G+ to begin with. It probably took me 10 minutes of refreshing each time to get something we wanted, which is not ideal if we're also watching the toddlers. But I was definitely vindicated with my wife over buying G+ that night or not!