I would never have thought I'd drive 30 minutes or more to an airport when I could drive 10 minutes and take public transportation to another airport, but I do. BWI's main advantage is that SouthWest flies out of BWI, so the prices are usually better. I've also never had trouble parking at BWI, although I often go right to the Express Service Parking (ESP) because they pick up and drop off right at your car, not just nearby. I find security and check-in are not great, but never terrible. There are also adequate places to eat in the terminal.
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