I have run stock saws for 25 years(50,550, 272,288, 372, 390 394, 395, 2100). I got my first "worked" saw from Simon last spring, and I have 20-25 tanks through it now. Here is my take on ported saws. They will run with a saw size up in a lighter handier saw. My 372 will cut with a stock 390...