I've used mine several times now, and yes, it's a chop saw. The blade is 4 inches in diameter. The main track (atlas in my case) is held in place with a clamp. I've never had the piece I'm cutting fly off, it simply drops off to the floor. No issues here.
Prior to this I used a dremel without a problem. However, I couldn't get all 3 rails cut straight across or at a 90 degree angle. Both of these problems are now resolved using this type of cutting too. Terry