Pros
Some of the reviews on here must be jokes... There are few jobs where you can make this much money and have so little stress. I will admit, based on the stories I've heard, McMaster-Carr probably wasn't a great place to work 10 years ago, but these days, my only complaint would be that some folks are still stuck in old ways of thinking. A lot of the restrictions and discomfort I see people writing about here are self-imposed. I've asked questions or experienced some of the things I've read and learned that they're either completely false or misleading at best. If you're a high performer, a job offer from McMaster-Carr is a golden meal ticket.
Cons
The high pay and unheard of benefits can really skew your perception of the world. What do you value when you feel no financial burden? Be prepared to question whether or not money and education are the end all be all. Free tuition, healthcare, maximum company-funded retirement contributions, and even tuition assistance for your kids. This company takes such good care of you it can warp your perspective of the outside world. If your friends complain about healthcare costs or saving for retirement, it might make you feel uncomfortable knowing that you're taken care of while others are going without. Highly recommend spending some time volunteering or giving back to the community as a way of staying humble. I can also understand why people are upset when they're let go, I've yet to see a company compare when it comes to the overall compensation package. Work here and you've got it made.