it's distinctly heavier in feeling than quilting cotton, so if you decide to use it, expect to feel the difference. also, quilting cotton won't wear as well. it's almost like men's workwear, not quite as tough as twill, but tougher than quilters cotton. it's got a different weave than twill, though. it's like a workwear shirt.
that's about as close as i can come to describing it.
if you wanted to make a quilt using all broadcloth, there's no reason not to. i just wouldn't mix them because of the difference in weight. i'm not the QP.