Pros
Benefits are pretty solid. 401k matching was recently removed, but that was atypical for a startup anyways. PTO is actually unlimited and employees tend to take an above average amount (at least in my department). We have a sizable customer base and they generally love the product. Engineering is of above average quality. Very good employee retention rate (employees are probably just happy in general). C suite is very transparent about financials and business dealings and decisions. The company culture has a handful of unique elements (e.g. annual company wide camping trip/getaway)
Cons
Offices have become significantly more cramped and overall seem dirtier and less nice than a couple years ago (SF). Catered lunch every day is nice, but the food is often mediocre to bad. Moderate churn in middle management. Building solutions for things like payroll and insurance means a lot of dealings with legislation and boring regulations, which can be uninspiring at best. Occasionally inept individuals become managers and do some damage to departments or teams. I'm slightly underpaid given my amount of experience and peer comparisons.