Avantages
The company culture is very welcoming, everyone is friends with each other, and there is no top-down authority at all. They are very flexible, understanding and kind. As interns, you don't get treated like interns (other than friendly banters), as the company gives lots of opportunity to work on real-life projects while also allowing participation in decision making. Colleagues are always helpful and fun to be with, with bosses (founders) that are easily reachable for any matters, personal or work. The culture that they have within the company feels really healthy and make it less of a terrible thing to wake up for work.
Inconvénients
There are much more responsibilities on the seniors, and as interns, we can see that they have quite a lot of their plate as they are always busy, so OT for them may happen especially during crunch times. The remuneration package is decent for interns, and also decent for other positions as far as I have heard from the seniors. Nothing special, but totally reasonable, and understandable as this is a smaller-sized start-up company.