This is such a Ford Vs Chevy issue that there is no right answer. Only what is right for you.

One random thought - I have to laugh at the comments about trailers being a pain in the ass to deal with. Dragging them up stairs, over barriers, shipping them etc. Cut me a break! Relative to other forms of touring Bicycle touring in itself is a pain in the ass!!! You ride a bike ladened with 30 to 40 pounds of gear through all sorts of weather up and down steep hills and mountains - you have to carefully pack everything you carry. You are grimy hungry and tired. After 6, 8, 10 hours of immence physical output, you need to put together a tent, and prepare an eatable meal. Then you get to sleep in a cold wet tent. Yet, dealing with a trailer is too much trouble? Seriously?

Nothing about bicycle touring is easy. That's part of the challenge. There is no easy way to bicycle tour. Only personal preferences about how to tour. MY preference is trailers. I like the just throw it on and strap it down factor. As well as the flexiblity of not being married to just one bike. None of the downsides of trailer towing is enough of a PIA to be a deal killer. That said, we use panniers as well. THey're OK, get the job done. We need to balance the load and saddle up one of the 520s to use them. Again, the downsides of panniers are not a deal killer. it all comes down to personal choice. There is no wrong answer.