Easy to admin. Love the upload ability since a lot of our schedule and similar info is already available - hated having to enter it all manually with the free version so we just reformatted a few things, did some copy/pasting and uploaded it.
Most importantly, our members loved it. Our member survey after the event indicated it was one of the things they commented on most, and it was all positive. Even had some non-users say they wished they had used it.
All this was a bit of a surprise to me, as our membership is a bit older than average and have not been "early adapters" of tech in the past. Some still don't use email! I ran it as a "soft opening" a year ago and didn't promote it. It worked well on the limited scale, so this year we got a sponsor, started promoting it early and quadrupled the number using it.
Users can upload photos to three different areas. I would probably like to see this reduced to just one, which I guess I can do simply by eliminating some of them. For example "Crowd photos" doesn't allow captioning, so it's not as popular. The social feed is definitely better for everyone that way. News Feed probably should be restricted because I had some people using it like the social feed.
We're a non-profit so it's really just all about engaging members and the sponsor/vendors who attend. We don't have to convert any of it to sales (I know...lucky us) but we did get a positive response from our vendors, so there's that.