I like both, but much prefer a sawzall if space allows. The sawzall makes less of a mess and sparks. And it won't leave a burr like an abrasive cutoff wheel.
It's a lot easier to follow a line if you use a 6" blade and angle the saw down close to the metal to increase the tooth contact.
They both have their places...I even like to use a jigsaw with a metal blade sometimes. However, everybody has their personal preferences...those are just mine.
