I fooled around with a 2 wheel kids trailer a few weeks ago. Didn't keep it, sent it back to the store. Here in South Carolina, there are no shoulders on the road and I kept on forgetting about the width and kept running my right wheel into the grass and dirt off the road. I guess you have to train yourself to remember that you have 3 sets of tracks to worry about if using a 2 wheel trailer vs one trick to worry about with a BOB, same as a regular bike.

Personally, I think BOB's are way overpriced for what they give you. For now, I'll stick to putting my stuff on my rack w/o panniers.

If I get some time this winter, I might play around and try to build my own version of a BOB.