Pros
I worked with Dover Solutions during my summer break and it was a great experience. I joined initially to learn more about marketing and promotions, but I learned way more than I had bargained for. Aside from marketing/promotions, I also learned about business overall, management styles/techniques and also got to attend a conference. I learned how to come out of my shell and network with colleagues in order to become better at my job. I really enjoyed the team that I worked with. You can tell that they're excited when they come into the office in the morning and they're genuinely excited to see you as well. I felt at home in the office and I hope to come back again after my final year of college.
Cons
Since the company isn't a large company, the CEO and managers have a lot more time to invest in you. However, that also means that sometimes you'll be asked to wear multiple hats if someone calls in sick or can't perform their duties. I feel like that's what makes you grow as a professional, though, but I can see how that would irk some people.