Pros
The job itself is very easy when you get used to it. Like a video game basically. You will probably encounter different things every day, so you are unlikely to get bored. If you like encountering messed up situations where everybody laughs at the messed up stuff, it's great. Most of the people working there are phenomenal, very nice and helpful- that goes for both managers and coworkers. The company is very nice to its employees compared to its competitors. Benefits are good.
Cons
You will not know when your start time is until the day before, every single day. the schedule is EXTREMELY unpredictable. It can be fun once you get used to it, but say goodbye to your social life from spring through fall. You will be paid less than some of the unskilled laborers you deliver concrete to. Most of the employees are awesome but some middle management and ambiguous positions are filled by very hardheaded people. Many of the job roles that work with you in the company are informal and have an ambiguous power relationship with you: you will have to develop an informal friendly relationship with them or you will suffer. (for example, mechanics; if you have a bad relationship with one, they will make you suffer a lot, or plant managers, same. Neither of these roles is your superior, but they have the informal power to make your work life horrible)