I attended RCTQS in 2011-2012 and am still working at Newport News. I can't give you any info about outside NAVSEA, but the more experienced folk already did that.
"HR has said that it's easy and uncomplicated -- basically just a certification that is required by the government, but, from searching on the forums, others disagree. Hopefully some people who have been there recently can chime in.
Are the days long and grueling?
Is the material hard to understand?
I have read on here the tests are brutal...
The school is not overly hard; however, it was designed for navy nukes and so for them it is really just another Navy qual school. Lecture, checkouts, practicals and tests. Speaking from a non-military point of view, I felt it was like a sophomore or junior level semester of college where there was only 1 subject. On the other hand, its 8 hours of learning and studying a day THAT YOU ARE GETTING PAID FOR. If you need extra help the teachers are really great about extra study time after hours and on saturdays (not sure if you can get paid for that.)
The days are only long and grueling if you let boredom creep in. Your class will probably have 6-12 other people in it; spend some time getting to know your classmates and make the learning fun.
The material can be hard at times. The two things to remember are: On the tests, rewording the answers is often a no no. Verbatim answers were waaaaay more important than I was used to in college. Second, If you struggle with practicals (practice jobs) have a teacher or fellow students practice with you till you see all the different ways things can go wrong so you know what to watch for.
Portsmouth has gotten marginally better, but then I live across the water and only had to park on the base for school. It can get pretty scary at night there, so make some good friends as soon as you can (classmates from Norfolk Naval Shipyard and Newport News Shipbuilding probably live nearby and might be people you would want to hang out with on weekends)
Good luck and welcome to the business.