Based on advice from this forum, and some other advice, I'll be at the Westin.
Forum provided me with good advice due to the free action at the Royal Beach Club - breakfast and dinner apps sound good and free at the Westin.
Local advice from my brother's co-worker who grew up in the area tells says that the Westin is the better place because of the proximity to San Jose Del Cabo. Cabo San Lucas is a bit built up - probably somewhat to the extent of Cancun, so I'll be at the Westin in September. I believe I reserved 2 rooms for 5 nights at 46,000 and change at the beach club. If by any chance you like to surf, this time of year can't be beat. Been to the CUN and enjoy it very much as I go back yearly, but I'm not as in to seeing Mc'D's when I'm on vacation out of the county.
Both places sound great though. August (and September) sound very hot, but I'll be at the pool or in the ocean, so I don't care.