Avantages
Heavy responsibility for all employees who want to work. Can know everything just by asking. Learning, risk taking, and innovation is heavily encouraged. All employees involved with key projects have high impact and sense of worth. I do more work that my friends at other companies, but not too much more and I seem to have gained much more knowledge and experience. Most engineers have broad skill sets.
Pretty interesting diverse environment. Wide range of education levels, ages, experiences, very heavy minority population with many languages spoken.
All engineers have the opportunity to become key employees and earn strong salaries, job security. This would be more difficult at a large company. I would take another job if it was competitive, but I am comfortable and still growing in my role.
Inconvénients
Growing company with rapid adoption of new processes and frequent restructuring to align with company needs. No longer run by Founder which increases day to day stability but might be less fun for some people. Work politics seem probably average but I am not sure.