I have 4 API Grand Slam Supreme climbers with the bar enclosed front.
I actually use them nowas hang on stands and simply put steps up to them.
I also have 2 Summit Goliath climbers that I use for my climbing hunts.

The API's are very comfortable with the full padded backrest, and seat.

The API's are not as stable as the Summit's, and they don't engage the tree as well as the Summit design. I have noticed the API's have the tendency to teter on a smoother bark tree instead of biting in like a Summit does.
I agree with all the complaints about the API chains, and shrink tube. It will not last long. I now use them exclusively as hang ons and it is not a big issue now, but when I climbed a lot with them it got chewed up quick.
The API's are decent stands but there are better out there.