Firstly, you will never not have OT. They often complain about paying it but they refuse to cut it.
I learned a few different jobs there but when I applied for advancement I was told I didn't look stable enough because someone else had decided to cross train me. There really is no advancement. Some people have been here 20-30 years and still do the same thing. I applied many times and they always found an excuse despite my track record and willingness to learn.
Management is a joke. Poor communication, split decisions made that affect only the bottom employees work-life balance, double standards, and the high turnover rate really should tell you that at least half of managers are to blame. Training is abysmal at best, certain promoted people have admitted they didn't directly ask for the role, others went mad with power.
Culture is somehow more cut-throat than sales. The old ladies that have been here for years won't hesitate to throw you under.
Hardest part is dealing with a never ending stream of drama.
You get PTO days, not vacation days. In larger companies these two are distinct. They finally made it so new hires get 10 days of PTO but they are not for 10 hour days, only 8, despite the fact that you work 10 regularly.
Only solid thing is the healthcare. Good and actually cheap. But not a well known carrier so it can be hard to find in network doctors.