I used to have a 15" Sven saw but got tired of busting my knuckles with it. It's also limited to small logs, 3 to 4" max. There isn't enough room inside the bow for anything larger. If I was buying another one, I'd go with the bigger one.
I also had one of those Gerbers that slides out. I really cussed that thing because I couldn't keep the blade from pushing in. I had to lift it clear out of the kerf on every push. It was a real PIA. I found the Sierra saw to be a good one although I need a new blade for it. I also have a folding saw that uses recip saw blades. Those blades are made for high speed power tools. They don't cut nearly as well as a Sierra, Silky, or other blades made for a hand saw. I have a Silky that really cuts but it's too heavy to haul around while hunting.
