Were were just there in early April and it was a zoo. We were only there for 3 days and the only day we DID NOT have trouble finding chairs was they one day we were at the pool by 10 AM. The other two days we were lucky to find one chair when we needed three. The pool was very crowded, which I did not like, but it did not bother DD very much. The pool is extremely cool, but extremely popular. We did see a lot of towels on chairs that were never used and families using one or two chairs and saving five. The CM's never removed any of the towels while we were there.
I think you have to decide how important this is to you in the whole scheme of where you stay. Also, don't forget that one of the best things about BC and BCV is the ability to walk into EPCOT and take the boat to MGM. We are hang out in the sun pool people so it would be a big factor for us.