Have stayed Beach Club 2x and Yacht Club 6x. Hands down we all prefer Yacht Club.
The Yacht Club quiet pool is always empty b/c of its secluded location.
Beach Club is filled with screaming, ornery kids with parents who don't always tend to their screaming youngsters running amock throughout the hallways. You can tell Beach Club is meant to be more kid friendly--the carpets and room fixtures contain characters from Little Mermaid. I do not like that, it seems to dumb down the whole grandness of the Resort.
There has been no character intrusion over at Yacht Club. Still feels like a turn of the century nautical grand Hotel, wheres Beach Club now feels like a Resort on Disney Property.
98% of YC rooms have large, full balconies; majority of BC has standing room only balconies.
Beach Club is, however, closer to the quick service food places and Epcot. But Yacht Club is not far away.
Yacht Club easily wins.