broadcloth comes in many different fiber contents/weights
is the one you are looking at cotton?
does it seem as heavy as the kona? since broadcloth is often heavier fabric a lightweight one may be just fine-can you see through it? the cotton lightweight broadclothes i have are heavier than my bleached muslin- and work just fine-
i don't really care for the poly broadclothes- but that's just a choice-
no reason to not take advantage of a great price-if it is as good as muslin-or better...i would think it would be- just the nature of broadcloth---