Best Tow Vehicles for Hybrids

I know I will get flamed by this but in reality there are lots of people doing what you are doing safely... insert flame war here...
Being from Michigan, I would consider a 2 hour drive across the border (from either Detroit or Port Huron. CanAm RV in London Ontario has been specializing in building custom hitches and road tests many of their setups at an old Airstrip nearby under extreme conditions. When was the last time your RV dealer took a towing setup to a proving ground and actually tried to roll it? They have done many many setups similar to what you are asking. I would talk to the owner Andy and get another perspective than the "you must be a slave to the weight calculations" answers you will get on a forum. Building a TV/Trailer package is far more complex than a little bit of grade 3 math on weight limits... insert another flame war here...
I am not saying you can do it with this particular setup, just that you should keep an open mind and look at all the factors before you decide.

1st, do you realize that the X17Z has about 400 pounds of cargo capacity? 2nd, what is the frontal area limitation on the Sienna? A hybrid will have over 60 square feet for frontal area.

When I got back into camping, I towed with a Jeep Liberty Diesel for a few years before finally getting a new Ram. The Jeep did it's job, although we were slightly over GVW with family on board.

I would check out the sienna forums. I believe most tow popups with theirs. If you want to tow a full height travel trailer, I would look for something a bit more robust.

DB has an '04 Sienna w/ 200K miles on it. He's towed his Fun Finder and family of 4 up and down the east coast.

I'm not saying I agree with this, but he's had success with this setup.

Well, to be completely honest? If you are looking at letting your teen-age kids dive the vehicle, you can expect 2 insurance claims per kid before they move out of your home permanently as adults!

My son was a good driver, but pulling out of our own drive way, a speeder (in a school zone, as the end of our driveway was inside a school zone), T-boned him pull out. The guy came up on him so fast, he didn't even see him coming!

Second event was in a parking lot. The kid just turned the engine on at the parking spot when someone slammed into the back end of the car when they were going in reverse! The damage to our car was pretty bad for a parking lot incident.

What I'm saying is, you can just expect something to happen. My suggestion.... really...!!!! If you want to keep your tow vehicle for pulling your camper, get the kids a different car!

With the trailers you mentioned hitched to a Sienna loaded with family you likelyhood of being overloaded goes way up. You would be far better off with something like a Tahoe, or even a 1500 series crew cab pickup.