Vantaggi
Smaller company spread throughout the U.S. Small offices make the atmosphere seem more like a small community. If you are up to it, you can learn as much as some one with a PhD or a Masters degree will teach. I have for the most part enjoyed working at ESI.
Svantaggi
Micromanagers are abundant. If you don't mind that environment, then you would love it here. The other down side is that any travel the company wants you to take is reimbursed. You have to fork over the money up front for hotels, plane tickets, car rental, meals, etc. Then when you get back, you submit everything and wait for approval. Even if you have to get something for work, it is the same thing. You go pick it up (after approval), then submit your expenses, then your get paid.