If two weeks causes a problem, it's because you've already got a problem; I've gone that long and longer with no trouble at all. I wouldn't expect a discharged battery in less than a couple of months or longer, depending on the load for electronics that run even at rest.
'97 SL500, 40th anniversary edition
'04 Olds Bravada (SWMBO's)
'06 Lexus ES330
'89 560SL (sold)
SL--Anything else is just a Mercedes.
(Kudos to whoever said it first)