I've had 3 dual axle TT and currently own a single axle toy hauler (20ft);
Prefer the single axle - much more maneuverable in tight spots (like some
gas stations); I can get into really tight sites in public campgrounds. Reversing into sites is much easier.
Weighs about 4,500 lbs loaded and tows like a dream with a Express 6.0 Van.
I just came back from a 5,000 mile trip to Big Bend - worked out great; in 30
years of towing, I've never had a blow out or bad bearing but then I keep up
with the maintenance and check tires/bearings regularly.