Jason- I respectfully disagree with Kerry. I'd take taxis.

Very few taxi rides (other than airport) will cost you more than $10, so I doubt your taxi bill will be more than a rental car would be. Plus, rentals have to be valet parked, and the line to retrieve them is usually as long as a taxi line. And then there's the whole drinking thing. You don't want to mess with Metro police, so if you plan to have even a few drinks on a night out, you'll want a taxi home anyway.

Just one man's opinion.