Vantaggi
Autonomy. If you like taking ownership of work and make difference, this is the place for you.
Growing business & tons of opportunity. Despite being pretty mature for a startup (4yr+), they're growing quickly.
Lean organization. No office politics, no bs, no face time, go home if you're done. (Of course don't take advantage of the system. These people come from actual hardcore finance and have put up with all the bs, that's why they care so much about culture. They will know if you're crossing the line.)
Caring management. Actually listens to what you want in your current job and the next. Tries hard to make it a reality.
Great stepping stone (if applicable). Every analysis you publish carries your name. Anyone who can Google will find articles with you as the author.
Kitchen stacked with food and coffee. Can't beat that, definitely a plus.
Svantaggi
Not #1 in industry (actually #2; Nerdwallet is #1).
Company name isn't well-known. Also hard to explain its business in a catchall phrase. Consumer finance? Personal finance? FinTech?
Small organization. If you want to learn workings of large organizations, this is not the place for you.