Otherwise, in my experience, it is utterly worthless for getting actual answers.
For instance, I've asked a total of 4 questions on the DBA Stack Exchange. Almost all of them were specific but easily generalized, weren't answered anywhere else. Three of them would have been easily answered by someone with good knowledge of the relevant products. (The other was only answered by significant trial and error.) On three of them, I was the only person to answer. Each of those took hours of research. On the fourth, someone else answered, but didn't appear to actually understand the question.
On StackOverflow itself, I've asked a single question. A moderator told me to do what I explicitly stated in the question I didn't want to do, and closed it as a duplicate.
The bounties are equally useless: earlier today I sacrificed 90% of my DBA reputation to get around 6 more views on my question. I'm pretty sure most of the views I got are from me refreshing the question.