We stayed in a preferred room at CSR for 10 days back in October and loved it. It was our second stay there, and would definitely return. We've also stayed at POR three times, but decided after our October visit that we prefer CSR. We've stayed at CBR once but it was a few years ago. Didn't care for it at the time, but with the recent refurb and bus changes, I'd be willing to try it again.
OP, to your point about the conference attendees, that's the one drawback of the resort for me. Its not big enough of a deal for us to stay elsewhere, but it is a distinction worth mentioning. During both of our stays there, conference attendees were abound, working on laptops and taking calls in public areas. While they were not noisy or problematic, it did burst my Disney bubble a bit because I also travel for work and it very much reminded me of one of my own work trips. We also noticed the attendees crowded the Disney Springs buses in the evening, and also crowded the indoor and outdoor bars and tables around the lagoon. We returned to the resort around 1am one night and the bar by the lagoon was still very lively and there was lots of garbage on the tables nearby.