I'd stick in the lower to mid-20s and with a tandem axle if you can because those tend to be a little easier to balance due to common locations for water tanks, etc. And for the record, this same exact conversation happens in another forum I participate on for a similar sized vehicle with towing capacities similar to the JGC V6. Wheelbase really does matter when it comes to the effects of wind, etc.what’s the max length you’d personally feel comfortable going with a car like mine? 20 feet? 24 feet?