I own Yeti and Bison. I am on the Bison Prostaff . Bison makes a great cooler and are made in America. Most coolers are measured by total volume (Yeti) and not interior volume. A 75qt bison would be the equivalent to a 90qt Yeti.
I do not see it being a problem. I like the latches. If you cant swivel them open you can just pull down on them and it will open like your typical YetiSo, I’ve been looking at the Bison Cooler website. I’m intrigued, but I am wondering if the patches are too low for sitting in the frame. Is it easy to open/close the latches when it’s sitting loaded onto the raft?
The Prospector would be a snug fit, or a perfect fit depending on your preference.Per NRS' website, the Otter 13 is 37" between the tubes.
I'd look hard at the Canyon Prospector 103, it's nicely optimized for raft use. (don't have one, but a friend does)