We have had great experiences, and not so good experiences at Reunion.
Our first experience was great, we rented a 3 bedroom condo from a 3rd party. We were allowed 1 day of waterpark access as we did not rent directly from Reunion. However, the condo was clean, in a good location, and had a nice view of the golf course. We didn't like that we had to find dumpsters for our trash, but that was really the only negative. We thought we'd found our new "spot" for when we visited Orlando
On our second trip, we wanted more waterpark time, so we rented through Reunion. Again, a 3 bedroom condo. It was nice, but the electric wiring had issues. 3 phone chargers were burnt up. However, we did get daily housekeeping, so the trash issue was solved!
For our 3rd (and so far last) trip to Reunion, we decided to go all-out, and rent a house with a private pool and hot tub, direct from Reunion. This trip was not good.
The house was not ready until nearly 6:00 pm, and the house, while pretty, had been poorly maintained by Reunion's rental management company. The pool had major issues (about which Reunion admitted they knew), and we again, had trash removal issues (we were told to put full bags on the porch, and they would be removed. It took 2 days for them to pick it up).
After this trip (Spring 2018), we have not returned to Reunion. It has not been definitively ruled out for a future stay, but I think I would rent through the third party company and not through Reunion.
I hope this gives you the info you desire. Feel free to ask questions if you need more info