Hours, hours, hours. Management likes to sell the point of "getting your hours" as a plus. True, you can make a lot of money, but be prepared for this job to be a grind. Like I said, 65-75 hours a week wasn't unusual, and I hit 90 hours on occasion. Spring and Fall were 6 day workweeks. Great if you're single, young and like to work. Not so much if you're raising a family.
Running jobs in the field can be pretty stressful. You have to work within the quote, solve problems as they occur and do this all while under the gun of a 14 hour driver limit. Plus, after you finish the job, problems can come up later and bite you days later. You WILL take the blame, not much interference set up by your superiors.
No much room for career advancement. Many of the guys I worked with have been doing the same thing for 7-9 years, with no real advancement or better opportunities.
Awful equipment and supply support. Trucks break down, which can leave you in some tough spots. I've broken down a few times, once at 7pm. Superiors left me hanging and I had to coordinate emergency service on my own. Didn't return to shop until 3am the next morning. Supplies are the worst, at least in the office I worked out of. "Reconditioned" means crappy second hand drums. Forced to use lab pack boxes which are bulky and awkward to move. All in the name of saving a dollar.
Overall, the people in my department were generally great. Management was a pain. Support was hit and miss. I moved on to a far less stressful job, half the hours at almost double my Harbors wage, However, I can also admit that I wouldn't have gotten this great job if not for my CH experience