Hi H1t M0nk3y,
I should note that I have never attended any of their conferences yet, but I've read most presentations, attended a Webinar (it was free) and read many of their slides, all those I found interesting including the archives.
What I found particularly interesting were the very technical and in-depth presentations, which BH focuses on. Whenever new slides are available I check them out, because I don't know why, but I associate the BH talks with high quality.
Defcon is of course, awesome too. It's cheaper and there are so many talks there, some of them are really really awesome too, but I primarily like that the presentations af BH, is suited for a 0day hackers mind and similar professionals or hobbyists who has been in the field for a long time.
I don't know about the training, but I have read about a few of their workshops and training sessions. Some of them looked really interesting, and again, very technical, at least what it says on their website. I might be completely wrong, but when I think of BH, I feel the same quality as OffSec provides.
That point of view could change, but I guess I'll have to submit a good presentation and get there to find out how it really is myself
I should note that I was disappointed with the DC 2011 presentations a bit. At least the slides I found on the website and thereby also the topics covered etc. Not what I expected at all this time.
Anyway, I think you should ask someone who has actually attended or taught at these training sessions
They are more qualified to inform you the pro's and con's, besides that it's really expensive just going there