I have one base and different tops. I like the bar kind for gun and a hand climber for bow. I really don't like to sit much since the deer always come from where I'm not looking so I stand with the seat either completely out of the way or down next to the base.
My bow has a long ata which makes it difficult with the bar a shorter one would eliminate the contact. Some day maybe. I like those short pse's.
The smaller hand climbers are tough to use. I picked up a LW top cheap because people just find them so hard to use, they are, but light and very compact. The open shots look the same. You could add in a rope climbing aid with those tops and get a much long stride going up. As it is it's like putting your forearms on a table and lifing you legs, pretty short stride. If you could reach up and put your elbows hire on the top it would be better.