Pros
Core & Main is a company where you have room to grow if you are ambitious and are willing to move. It is also a company where many people are content in staying in the same place for years. What you choose to do is up to you. Core & Main typically hires from within, so you do have the opportunitiy for advancement, if you are willing to put in the work and to be geographically flexible.
Cons
Your experience is going to vary massively by branch and district. The corporate offices tend to operate with a light touch and the local branch managers have a lot of leeway in how they run their branches. The same applies at the district level. Each branch will have its own culture, customer service philosophy, work/life balance, etc. Make sure you do your research before applying. Honestly, a lot of people do not find waterworks very interesting. Outside of the corporate offices, Core & Main is not a company where you can sit in a cubicle all day and ignore everything outside the office. Its a construction distributor, so you're serving their needs. Some people may not enjoy the mix of blue collar and white collar work. The pay is not necessarily great for a lot of positions. It is on you to negotiate a good salary. Core & Main does run a lean operations so this may be difficult.