Pros
The people are super friendly and supportive.
You can ask for help, and you will get it.
They give you ample opportunity to do well, to try out different things and to excel.
Pay is as per industry standards.
They are good with helping you learn and pick up new things. They are patient, and they actually give you the time to learn, and they work with you to ensure that you have all the resources available to get better.
They are appreciative of good and hard work.
Cons
The only con for me was that in spite of being a start-up, their culture was a mismatch for me. They were more about following rules than about getting work done. They expect you to work overtime and extra when needed, but won't give you the leeway when you have lesser work. That's fine for a lot of people and they thrive in such cultures; I don't.