Steve-
I HIGHLY recommend a load leveling hitch. My first two years I towed with my Jeep Cherokee. It is similiar to the Montero in wheel base and tow rating. Before the hitch, I had to really make sure the trailer was loaded evenly (remember I was only towing a CRX). I figured with my steel trailer, job box for storage, and car, I was towing about 4500 lbs. The hitch made a world of difference. You could go 70 mph down Interstate 43 to Blackhawk with only one hand on the wheel. Before the load leveler, the Jeep was all over the place. Towing also puts alot of strain on that size platform. I finally said screw it and bought a year old Excursion in the spring of 2003 and thats my current tow vehicle. I agree with the previous posts. Get something low, with long ramps and a tail that is angled down rather than flat for easier loading and unloading. I have a winch, actually a boat winch, that we bolted to the front of my trailer. It makes life so much easier, especially if the unthinkable happens on the track, and the car can't be driven on the trailer. Definately go with an open trailer, and Greg makes a great point about being able to open the car doors over the trailer fenders. Hope this helps.
--Bill