I want to buy a miter saw (craftsman, dwalt, ryobi...etc) so I can cut exhaust pipes once in a while.

How big of a miter saw should I get in order to cut 3" OD exhaust pipe?? 10"?

OR is a 14" chop saw mandatory? I like the miter saw because its more versatile for home projects..

 

you should get a chop saw for sure. not a miter.

just get the harbor freight one for like 40$. its lasted me a few years now, and works fine for occasional use.

 

a metal cutting bandsaw from harbor freight is more versatile for thicker materials and can pipe with ease.