Good companies
Ya know, when I left professional aviation I had about come to the conclusion that all aviation companies are bad news. I felt that way primarily because of the disrespect and dishonesty exhibited to pilots. Overall, that probably will never change. I've since reflected on my blanket conclusion about companies and realize there are some which are good.
You probably don't want to be a career instructor, although there is absolutely nothing wrong with that. The business needs good, dedicated flight instructors. The foreign airline training operations in the U.S. seek out dedicated flight instructors and treat them well. Two examples are Air Training Center Arizona in Goodyear, Arizona, and International Flight Training Academy in Bakersfield, California. IFTA is a clone of ATCA. Facilities are state-of-the-art, equipment is first class, and money and benies are excellent. Good students, hand-picked by their airlines.
I worked for FlightSafety's school in Vero for just over a year ten years ago. I left primarily because I didn't care for the disrespect I was shown. Since I was there, new managers have taken over and I understand the place is better. Pay is alright. Equipment is very well-maintained. They are taking delivery of new Seminoles. Benies include good health and a 401-K. Facilities are excellent. Cost of living in Vero isn't bad. Good place to work at for a while, maybe longer. I hear other FSI facilities are good places at which to work.
ERAU was the best aviation job I had. Pay was excellent, with incentives to earn more money. I don't recall if there was a 401-K, but with a union there now I'd bet it has a retirement plan. Well-maintained equipment. Stimulating learning environment. Downsides included problems getting aircraft, which made it hard to work at times, and a lot of ridiculous monkey business.
A lot of people say that SkyWest is a good company. I've heard that EJA (Executive Jet Aviation, not the P-F-T outfit) is very good.
You need to evaluate a company in terms of your needs. Don't expect much from a place if you are just looking for an experience-building opportunity. Look at it in terms of professionalism, facilities, pay and longevity among employees. One other clue: I've learned that I can tell a lot about a place from its H.R. function. If a place seems disorganized or frantic or in any way untoward during the interview process, that's the tip of the iceberg. Chances are, you won't be treated right.
Good luck with your job search.