I am looking for suggestions and advice to reduce the amount of trailer sway and push.

My tow rig is a 1999 Chevy Tahoe (4WD), with an 18ft open trailer. Total weight of the trailer and car is
about 4500lbs, with probably another 1000 lbs in the back of the Tahoe (tires, tools, people).

On the prior tow rig that I used (1995 Jeep GC), I installed air bags in the rear to raise the rear when towing, this did help reduce the sway and push.

Instead of air bags on the Tahoe or helper springs, would weight distribution hitch be a better
solution?

Air bags or helper springs would be about $300.

I found Curt Round hitches for about $160 plus shipping, and Curt Trunnion for about $286. Are there dramatic differences between the styles and prices of these hitches?

Thanks,