I recently did my first overnight trip with a Burley Nomad, and it works perfectly for me. A couple of perceived advantages over a one-wheeled bob-clone or panniers:
- Balance: I feel that it takes a lot less work to haul the same load in a two-wheeler than it would with panniers or a one-wheeled trailer which requires effort to balance. Uneven loads make very little difference with the Nomad. If the bike tips over, it won't take the trailer with it. If you dump your bike or lean it at an odd angle on a hill, the trailer won't stress your frame. If you're aggressively pedaling up a hill, the trailer won't swing back and forth. The trailer takes almost all the weight, further reducing stress on your frame and rear wheel.
- Maneuverability and and off bike: It's really no wider than a pair of well-stuffed rear panniers. I expected to have to constantly worry about tracking a wheel off the road, over potholes, or tracking too close to a rail/post and getting the trailer stuck/flipped. In reality that has not been an issue at all. It tracks over small obstructions often enough, but it's generally barely noticeable, as the attachment arm dampens must of the jarring. I haven't had to adjust my riding style at all. The hitch isn't fussy at all and can be attached with one hand. The trailer itself is easy to move around loaded, and makes a handy cart when off the bike. Mentioned this, but it's also easier to park.
It should be mentioned that while I love the trailer, I can't deny that it pulls down my average speed significantly. Maybe that'll change as I get used to it. More importantly, I don't care. I'm more of the meandering sort of tourist with no need to get anywhere fast. The trailer fits my style very well because despite slowing me down, I actually feel less exhausted late in the day, probably because I'm not having to balance heavy panniers constantly. It's also not truly weatherproof, but that's nothing a tarp around your gear won't fix. I rode for hours in heavy rain, and no significant amount of water got in. I'm still using the big squishy stock tires on the trailer, but I plan on putting something slicker on it.