It depends I suppose on what you're cutting, but hacksaw speed it ain't. It will cut any and all types of masonry, stone, metal, wood, glass. I bought one last year and tried it out. The blade is quite similar to ones you can get at the hardware store for a sawzall reciprocating saw to cut metal and masonry with, so nothing special there, but the handle was pretty robust and seemed stout enough for the task.

I think there's a thread I started on this thing about a year ago when I got mine.