I would guess the two most popular are Summit and API....I have 2 APIs...
They have two advantages over the Summits that I have seen...One they have a padded shooting rail that can be taken off...Summit used to have a V-type shooting rest...I didn't like it and don't see it offered in Bass Pro anymore....Another advantage with a API that I have found...you can easily lock it to the tree....and still climb with it....Just buy 4 long shank locks and replace the pins that go through the roller chain with....I left one around a tree all season, I share this stand with a buddy, that way either one of us could use throughout the season...Good luck