Personally I use an older Summit Viper. The newer ones have some refinements, but the basic qualities are the same. Without suggesting it is the best I have found that generally speaking for a stand to be comfortable it has to have a good seat. It also must have some sort of arm rest. The arms hanging from your shoulders with little or no support is what wears you out.

The bar around the front, although not a necessity, does allow you to lay the bow in front of you when sitting and gives some sort of confidence when you are standing. I usually press a knee against the bar when standing so it gives me some stabilization and basically lets me know where I'm located on the stand.

I bought this stand about 7 years ago after having several without the bar and it has helped me stay in place for hours on end. I used it in Illinois a few years back and although tired at the end of the day I wasn't worn to a frazzle. And I don't care who you are. 12 hours a day without coming down and you are going to be tired, but at least you don't feel like not getting back in it the next day, and the next, and the next. I think I got more sleep in the stand than I did my bed.

Setting the seat height is important, too. Too low and the bar can get in the way. Get it right and you can shoot from a sitting position sometimes. You certainly don't want it to be too low, but too high and you don't get the support for your arms either. Trial and error for this.

There's also the physical weight to consider, too. The 20-21# of the Viper is just about my limit.