I can think of a lot of reasons "not", but the easiest one is using flux core on sheet metal is messy and does a poor job. You will be grinding most of it off or blowing holes through the metal.
A nice 110v gas set up (like the Hobart 140, Miller or Lincoln) is far superior for sheet metal.
If you are serious about learning to weld, you will kick yourself for buying the HF one, once you get a little experience.
Other opinions may vary...
Dale
