if you can, I would suggest trying both 1 and 2 wheeled trailers. While I havent toured with trailers, i have a lot of experience pulling kids in 2 wheeled ones, as well as 1 wheeled trail-a-bikes. I vastly prefer 1 wheels as they track nicer, dont shimmy when hitting bumps (or one wheel in pothole, 1 not). I have pulled a 60lb kid on the 1 wheel thing, which I am sure weighs more than a Bob trailer, and it worked well, even over distances of 30-40km (not that a 2 wheeled one wouldnt either)

I also liked, and can see for touring, that a 1 wheeler is narrower, so less issues with worrying about clearance with stuff (walls,cars etc) also probably easier to stick into a car etc being narrower.

guess you really must try them on your own, I know which way I would go. That said, a two wheeler might be better for big bulky stuff, I personally would prefer the narrow tracking riding characteristics of a 1 wheeler.