Pros
Tech stack is awesome. Sometimes free lunch. The developers they have are of a high caliber. The CEO has his head on straight.
Cons
Its like a dysfunctional family reunion at the management level. Some of the higher ups refuse to even talk to each other directly, almost using the CEO as a proxy. Lots of turnover should be a red flag. Way more work than can be accomplished by the team, expectations of working way more than one should even for a startup (up to 90+ hours in a week if you take Sunday off). No clear goals even on a day to day level. Projects are scrapped when mostly complete due to a "change in direction". Scrum is a joke here, as its simply one person deciding how much work each sprint will encompass with no valuation of previous velocity; Complaints in retrospectives are explained away / ignored. Little to no respect for employees. Sometimes, it even devolves into public shaming and yelling by management to employees.