I'm helping a friend plan a trip to Washington DC for a meeting there. I'm trying to convince her to take a connection to fly into DCA rather than flying to IAD nonstop because from what I hear, IAD is really really inconvenient to get to downtown DC? She's looking for overall trip time/convenience (which means ground time as well). Any thoughts?

and side note: she managed to get her driver's license suspended so renting a car is out of the question, and she doesn't want to pay for airport shuttle/taxis, and she's going in March/April so ORD weather shouldn't be a factor.