My opinion is that the 22' is a better fit for the X for a couple of reasons. First, the 16 footer has a 8' width, whereas the 22' is 7'3" wide. That makes a difference when it comes to consumption at highway speeds, and based off of some notes from a single (somewhat unreliably consistent) source towing a 16' Sport with their X, consumption is as high on that camper as it is on my 22'.New model X owner who just upgraded from an S. Many reasons for the change, one of which was the ability to hitch bikes and snow gear in the back. Now that I have the car, I’ve been toying around with the idea of towing a trailer, a 16’ Airstream. This discussion has been quite informative, being a novice at trailers. Questions for the experts here. Seeing as WD seems to be a no go and that towing a 22’ seems to be challenging without WD, would a 16’ Airstream be much easier to tow? Would the shorter by 6’ and lighter by what 800 pounds or so make a big difference?
Second, I still think you'll want some kind of sway control, and most sway control comes with a weight distribution hitch. Many people tow without WD. Tesla is towing their 22' Airstream mobile showroom as a weight bearing setup. I'd love to get a photo of that, by the way, and see if they upgraded the Bosal. But the point is that many people tow with just the ball, and swear they don't have trouble. I am a bit risk-averse, and the more you read about this topic, the more you'll see that experts definitely suggest some form of sway control.
There is a WD hitch option where you could get the benefits of anti-sway without putting strain on the receiver. That would be the Hensley Cub. In hindsight, I think it would have been a much better choice than my Equal-i-zer.
In the end, just my opinion - if you're towing anything with reasonable weight, you should consider upgrading the hitch on the vehicle.