Towing, we did experience a slight left to right buffet on the interstate going about 55. Oddly I found that if I accelerate to 65 the buffet went away. The FJ with the overlander seemed stable at that speed. We were just using the stock 1964
towing hardware on the trailer. A modern day anti-sway/weight distribution hitch would probably eliminate the buffet entirely.
She had plenty of power left over at 65 to pass other slower traffic. In fact I was kind of enjoying going past people in more modern RV's with my old camper. It felt good to know she had a little umph left if I needed it.
We've had ours for almost three years now. We bought is used. I can say in the time we've owned it, we haven't had any mechanical trouble. For all my gripes about comfort she's a sturdy little vehicle and much more capable than she looks. The only maintenance we've done is the standard oil changes, wipers, tires, etc.
I like not having to necessarily own a big tow vehicle. So when I finish out our Overlander I am going to work very hard to keep it light. I am going to build all the wall partitions like they were meant for an airplane out of spruce and thin ply, etc.
I'll keep you posted on that. I will be curious to see how the FJ tows the overlander when the overlander is finished. Of course we have a Dodge Ram pickup as a backup if it proves more than the FJ can deal with.