Pros
I worked for Skimlinks for a number of years, and like any startup, there were certainly ups and downs (that's what you sign up for if you want to join a young tech company) but I left feeling exceptionally grateful for the friends made, experience garnered, and significant responsibility I was given at Skimlinks.
These are sociable, supportive people doing innovative work. Employees are encouraged to speak up and heard, while management is impressively transparent about numbers, investment and other high level discussions. It's a great place to be if you want to learn about how companies are run.
Over the years, junior team members have consistently been promoted to more senior roles, and it's the kind of place that will look to its own before trying to recruit from elsewhere. That's valuable.
Cons
Skimlinks does its best to innovate quickly, which means that priorities can change as circumstances do. If you're the type of person who needs to know exactly what they'll be doing in 18 months time, it may not be a great fit.