I tow a 29' TT that weighs about 8500 with the Equal-i-zer 1,200/12,000 hitch. It tows perfectly at all times. My tongue weight is around 1,250lbs.
I would find out what the tongue weight is and then decide on a 12K or 14K model.
Honestly it tows so well that I couldn't ever consider a different hitch, there just isn't much, if any, room for improvement. I don't ever fell the trailer, even in 30mph cross winds at 65-70 mph.
I often wonder about people that talk about night and day differences with the Hensley. It makes me think they either had a very bad setup, or it wasn't setup correctly. That could me more than just the hitch, to include TV tires and suspension.