Instructed 4 years. 3 years part time in while in school, 1 year full time after graduating. This was in the late 90's. I actually, for the most part, enjoyed it. The pay sucked, no bennies. But, I made my own schedule, really enjoyed teaching, enjoyed seeing my students succeed. I worked at a local FBO that stayed busy, but wasn't a pilot mill by any means. I certainly learned a ton over those years.

But, what BZNpilot248 said above rings true. I never went through the single pilot, IFR cargo over mountains type stuff. I think that would have been invaluable experience.