Well.... Mach3 just does not follow that description very well. Good intentions. But it leaves a lot to desire. Angular settings and look ahead are not effective. Maybe on a metal mill with 10-30 ipm but the second you start to go up in speed the model fails for various reasons not all Mach3's "fault". The only salvation is to regulate feed and tune the motors till the results satisfy the need. In a plasma cutter you can adjust the motor tuning much much more aggressive regarding the acceleration compared to a heavy gantry of a larger router. You can fly around the corners like in a bumper car, compared to a semi truck. The more aggressive the acceleration the less the rounding. That together with a reasonable speed will work fine. The look ahead and the angular functions will give you gray hair. Even if the angular function would yield the correct result, it would be nice for a router,cutter, but horribly wrong for a plasma cutter who needs constant velocity to maintain cutting quality. Even in case of a router/cutter a speed change without cutter speed change is a potentially bad thing. But there are limits to Mach3.... understandable limits!
So... long story short, tweak the acceleration as aggressive as you can without loosing steps or stalling the motors and you will be much better off.
Lemo