Hello all-- You were all so helpful on the first question-- time for a second!

Planning on doing a trip on the C&O & GAP this summer and I cannot decide on taking the panniers or the BOB trailer. I have both, it's just a matter of which one will work best on the trails, particularly the C&O since it's a bit choppy in places.

Thanks everyone ahead of time!

Well, when I did the C&O/GAP with a bunch of folks from this forum, 2 had 2 wheeled trailers, 3 had BOB's, and about 6 used panniers. Everyone made it, but the folks with the 2 wheelers had the most problems on the C&O. Other then that, the BOB's did just as well as the panniers and I never heard anyone complain about their chose of equipment. Everyone complained about the trail conditions ;-) Either will work, it more personal perference.

The issue with the C&O is that it is, effectively, single track in many places. There can be tall grass in between the two tire tracks.

Can't see a huge difference between a BOB and panniers that's specific to the GAP/C&O. Definitely don't use a two wheeled trailer. Make the choice that's best for you without worrying the fact you're on the trail/towpath. There are other threads on general differences between panniers and trailers that you can read to your heart's content.