I have a API Bowhunter and a Lone Wolf Climber and my hands down favorite is the API. It climbs very easy and is very comfortable. The Lone Wolf packs and climbs nice but the seat is terrible, if they could come up with a better seat this stand would be really hard to beat but until then my API is my favorite.
Someone mentioned the hand climbers being hard on the upper body. I do not agree with that, If used properly all of the climbing is done with the legs not the upper body. I just use the hand climber to hold onto and then bring my legs up so the legs do all of the work.
Just my 2 cents worth, Have a great day!