I've spoken to STE's from both Northrop Grumman Newport News and Norfolk Naval Shipyard. NGNN has a pretty bad reputation locally, based on how they treat their people. Speaking to a Shift Test Supervisor at NNSY, he said he left NGNN for NNSY and essentially doubled his paycheck. I pulled aside a recently hired STEC (STE Candidate), and she said that when she was going through hiring, they required a degree or that you at least have been a Chief in the nuke field. Speaking to the few STE's at NGNN I know, they said they're hiring any former nukes, regardless of rank. You wouldn't be a STEC, but you would be the rough equivalent (they have two kinds of 'stec': MT and ET). The information above about pay seems right.
Speaking to a recently-qualified STE about pay and training, he mentioned a lower pay at the beginning, but that it is GS-12 once you qualify. Qualifying takes anywhere from a year and a half to two years, and is not really based on how quickly you try to get done with it. You have to wait for various class-ups, etc.
Hope this helps!