Well, its been done. I have a hitch on my 1st gen box. xB2 has a bigger engine and greater body mass, I'd feel more comfortable trying to pull a trailer with a xB2 then my own.
This is the hitch I'm using, I wanted one that would hide behind my bumper, I hate to see a hitch on any car.
Hitch on ebay
I use my hitch to drag my waverunner (about 700 lbs total) to the water and back. Only short trips of less then 10 miles. I also use it for a bike rack. With the bike rack, the xB has a bit of bounce to its step, but other then that, no noticable difference when starting or stopping. When you're trying to pull a trailer, however, you feel it, starts slow, stops slow, breaks lock if you press too hard. All in all, I don't recommend it as an everyday thing.
Pulling a trailer is sort of like driving with a full load of people in your car. Imagine having 3 passengers that weighed 300 lbs in your car with you. You'd feel the difference when you pressed the gas because the extra weight puts more strain on the engine. Now imagine those 3 passengers pushing your car forward while you're trying to stop. If your trailer doesn't have breaks, the trailer will continue to push your car forward as you break.
There are people that have pulled 1000+ lb trailers across states in first gen xB's. Some say they're not bothered by it and don't even notice it back there, other say what I say "I don't recommend it".
If you're gonna pull a trailer, the lighter the better. Find the lightest trailer available, or have a custom aluminum one made for your application. Electric/hydraulic bracking system wouldn't be a terrible idea for heaver loads. Many people may consider that overkill. Though, I wish my waverunner's trailer had breaks.
The xB will pull weight, but I don't recommend trying to move much more then 1,000lbs. It could damage the frame or engine.
This isn't my car, but I found it when I did a search of clubxb.
Re: Xb towing? 
