I've been on it both as an AD member and currently, as a dependent. I had no issues as AD- I did have 2 babies on AD, and for the most part, my care was very good. Now, with 3 kids and myself on it as dependents, I am very happy with our care. Everything has been paid for except for one type of treatment for my son, but it is also not covered by most other insurances, so it was several hundred dollars out of pocket. However, when he needed surgery, we didn't pay a penny. At our current duty station, regular care is at the MTF, but pretty much any specialty care, we are referred out (which has been a first for me), but we have not waited longer than a week for our referrals. Most of them have been to great doctors, very, very close to our house (we are in a major metropolitan area, so I'm sure that helps with availability). Personally, I don't really have any complaints, other than a few annoyances (which I'm sure I would have with any other insurance, except I would be paying premiums, co-pays and plenty of other money, as well).
The dental actually covers the 2 cleanings/ yr, and annual check up, along with 80/20 coverage for most basic stuff like fillings. They do not cover anything for braces for people over 23, I believe (though it might be 21). Then again, it's rare to find one that does cover them for adults.