Growing pains are evident, especially when it comes to process and procedures (or sometimes lack thereof). However, as eluded to in the pros, the ability to help shape the direction of future goals and drive future success is a strong mitigating factor to this.
Ownership is a requirement here. Not necessarily a con, but a heads up to anyone who just wants to just wants to sit at a desk and execute on an already delivered plan, that won't always exist here. For people who want to help shape the future of a team, this is honestly a plus.