For those who care -- M lounge at the Marriott is open 24/7 for drinks/snacks, BUT has no bottled water. Renaissance has bottled water, but adheres to more typical lounge hours. I find the evening offerings at the Marriott superior to the Renaissance, and I'd say they're a wash at breakfast (although if you like hot sauces, the Marriott stocks a rotating variety of interesting options). I may try the Sheraton for my next stay (which are usually multi-day for work despite being at "airport" properties").