Weird question, I know, but I need a new apartment and trying to decide between those areas. Money isn't really an issue.  

Nice restaurants
Reasonable nightlife for the 40 something crowd
Bike trails,parks etc
Metro access
Civilian milfs or divorcees
Incall or outcall from some of the lovely providers on the site

Any suggestions would be appreciated.

Just ask yourself, do you want to live in Virginia or Montgomery County? Both locations are nice and accommodates your listed amenities. For myself I would say, Bethesda would fit the bill

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You may know that Bethesda has been undergoing a building boom in the past 10-15 years and it has accelerated recently. There are several spiffy buildings (both condo and rental) that just opened and a few more almost finished, so there are lots of choices just south of the Metro. Plenty of good restaurants, shops and a great public library (librarians!). The area north of the Metro is starting to see a makeover now as well.

For the other options, Pentagon City is a bit closer to downtown and Virginia has lower taxes. Court House and Clarendon also are nice.