You shouldn't come into this DVD expecting any kind of real documentary whatsoever. If you're watching for the T&A, OK, it's got that in spades so you can probably not bother reading the rest. Personally my girlfriend and I were hoping for an actual focus on the the burlesque show itself, being fans of the genre, even if the SGs loosely interpret it. There is very little of their performance shown and it's only in brief teaser clips mostly. Almost all the behind the scenes stuff was either interviews that just felt like advertisements for the Suicide Girls website or was just more nudity for the sake of the camera.
So basically it's a softcore nudie flick and an advertisement masquerading as something else. This is not surprising given the self-promoting character of the man behind the girls. Just know that if you want naked girls, this is probably fine for you, but if you're looking for some actual documentation, skip it.