Pros
100% Tuition Reimbursement, very good medical benefits, fair pay, you don't take your work home with you. They helped me with the down payment on my house as well as gave me a monetary gift when I got married. The culture of the company is that they do care about taking care of employees and if you do your job and don't screw around it is a fine to place to work. I think some departments are better than I others my department was small and not run by an "MD" so it is a good place to work.
Cons
"MD" stands for management development. Management development hires are young people hired right out of select colleges around the country at really high starting salaries for the purposes of becoming the company's management. In my time here I'm aware of a only 1 or 2 people who weren't hired as an MD being promoted into a supervisor position. Obviously everybody is different and I was never directly managed by an MD but I didn't like how this worked and I was not impressed by the most of MDs that I dealt with. They are smart and motivated people but what caliber of person goes to an Ivy league school and then takes a job at McMaster-Carr? Don't you want to do something more with your degree? I've earned a masters degree while at the company and have received positive reviews every year I've worked here and have not even heard mention of a promotion. I found this to be really demotivating.