I have read many of the horror stories about USSD and as a current student at USSD thought I'd throw in my two cents. I have been at USSD for a year now and am a blue belt. I wont deny that a lot of the McDojo's qualities are there, I recently went to a USSD tournament where my old sparring partner who joined USSD's instructors academy a few months ago and is probably a brown belt ( as a jr instructor he has to wear a red belt and is not allowed to reveal his rank until he gets his black belt ) walk all over the other jr instructors, some of whom were 1st dans. Now don't me wrong he is a good figther with a military background, I learned a lot sparring with him and from the advice he gave me, and I miss sparring with the guy, but it was a bit disappointment to see that I could give the guy more of a challenge than the other jr instructors. I also think USSD charges a lot more than they need.
That having been said though, my instructor pushes me during every class and I have never left a belt test without my gi caked in sweat and breathing heavy. My instructor expects a lot out of me and even held me back from a belt test because he felt my attitude wasn't right at the time. I like my instructor and am learning a lot from him and he is the reason I've stayed with USSD as long as I have. Bottom line is there are a lot of crappy instructors at USSD, but there are also some really good ones, and the style itself is pretty good since it is essentially the same as what Fred Villari teaches which is very similar to what Nick Cerio taught.