Pros
Riot is not for everyone, in fact it is not for most people. If you're looking for a cushy, stable job where you can carve out a comfy spot for yourself, don't apply. If you need to have someone regularly delegate assignments to you and tell you what needs to done, don't apply. If you're resistant to stepping out of your comfort zone to try something you've never done before, where there's a possibility you'll fall flat on your face (sometimes in a very public setting), don't apply. If you like to work in a highly structured environment, where you knew exactly what's expected of you and there's very little ambiguity involved in your day-to-day activities, don't apply. Conversely... If you're a star performer who wants to work in an environment with some of the smartest, most accomplished people in the world, this is the place for you. If you are open to hearing ongoing feedback (both good and bad) about your performance/attitude/results/diction/demeanor/behavior on a regular basis, this is the place for you. If you're fairly comfortable working in ambiguous situations where there may be no right/correct/standard way of doing something (sometimes because Riot's facing problems very few other companies in the world has ever dealt with), this is the place for you. If you're able to stand your ground and push forward with what you believe is the right thing to do, even in the face of intense personalities, conflict and sometimes derailment, this is the place for you. If you have a record of seeing problems, owning solutions (not just the idea but the execution), and persuading some of the most insanely busy people around to buy into your solution and support you, then Riot is definitely the place for you.
Cons
The cost and traffic congestion of living in LA is horrendous. There is absolutely no other job I would have taken that would have outweighed the crappiness of living in LA.