I am working in CodeNation and will try to answer this question based on the experience.
1. First thing first, its extremely fast-paced start-up like company where people have to really perform a lot better than they would have in any other standard company / start-up. CodeNation offers flexible timing for employees, but developers generally work long hours to meet the deadlines, so, amount of time you spend is dependent on your project and its deadlines. I will say, generally people spend 60 hours/week working but it varies a lot from time to time based on the status on project.
2. Problems they solve are more difficult than usual which means people either have to be / become extremely technically sound to solve them. This is advantage as well as disadvantage depending on what kind of person you are. If you want a peaceful-unchallenging life, CodeNation is NOT for you, please join a big service company instead (and preferably ask to be on bench). If you love a challenging-fruitful life, CodeNation is FOR you.
3. Career - CodeNation offers good salaries and trains you to be the best 'Problem-solver' which means you end up working on and knowing more technologies than 4 average developers combined.
4. Work hard, party harder - CodeNation believes in partying harder, encourages it and sponsors it.