Saw this interesting idea recently. I have done airbags and load distibution bars. Pros and cons for both.

This looks simple and easy.

Found it at www.hell-ya.com

I think that would be a bad idea, it does nothing to stabilize the vehicle side to side and in an extreme situation could maybe unload the rear suspension.

It's an interesting idea.

I could see it doing as Mark says, descending a steep hill, if the trailer hitch scrapes on some of them, it would totally take the rearend off the ground, then all that weight would have the potential to free roll. Good to see people thinking though.

I have seen a similar setup on a horse trailer. The owner said it pulled good, but forget about backing up

I don't know if that's such a great idea.....

Any positive support at that point will act to unload the drive wheels. It will effect braking and handling.

I believe the original design intention was for RVs that had real crappy tongue weight specs, but owners still wanted to pull a trailer.
Personally I'd rather have as few extra "links in the chain" connecting my tow vehicle to my trailer.

What happens when the tire(s) blow out at 70mph.

Even their FAQ denotes "this is a temporary fix to a temporary problem".

I can't imagine it would work well with surge brakes either. If you are going around a curve, and hit the brakes, the trailer is going to push the rear of the vehicle sideways. This is already an issue with surge brakes, much less something like this that moves the point of the hitch back what looks to be 12" or so.

Not sure I'd like it either. Haven't seen one in action, that's for sure.