BDF - BWI & SW have been a bad experience for me, even prior to 9/11. Since then however, it has been a total disaster in terms of lines, more lines and frayed nerves.I was there 2 weeks ago and it was horrible. I leave for BWI again tomorrow. Getting there isn't the problem (no cxn) but Thursday evening's return will be a horrible.
The new security policies are, IMHO, effecting SW more than anyone else. Having to print a boarding pass is contrary to everything they believe. Having to show that paper boarding pass to board the plane is also slowing down their turnaround time. The last 4 SW flights I have been on have all been late between 15 and 50 minutes. That is something new. The worst effect of the new {useless} security is that many travellers, especially leisure travellers, are arriving at the airport 3 hours before flight. That means lines are starting to form at the gates up to 2 hours in advance making it even more difficult to secure a good seat.
SW has made a fortune by taking people out of cars and onto their planes. The time it now takes to fly SW is diminishing the advantage of flying vs. driving on many of their short haul routes.

Having said all that,I would still recommend you give them another chance.Maybe you can connect thru STL,BNA or MCI and have a better experience.