The main difference between an abrasive chop saw and a TCT saw is the RPM. Abrasive saws spin too fast for the metal blades and will wear them out/ damage them quickly. As far as the Evolution saws, the orange saws are their economy model intended for box stores while the blue model is the nicer, higher-end model. We sell the blue Evolutions saws here if you are interested. We have 3 different models to chose from.
Late to the party, but for what its worth, I had an old miter saw that was maybe 100.00 when I bought it 5-10 years ago. A cheap ryobi one. I put a 14" metal cut wheel on it and used it for my exhaust. Worked just fine. Some of the plastic guards became a little charred and I took odd the sawdust collection bag, but it was effective enough.
I've put the wood blade back on since and it works just fine.