Great career starter. Horrible work life balance.
Pros
SD is a fun company. The work is tough, but rewarding. If you're looking to learn and dive deeply into software development / Magento / Shopfiy , you're going to like it there. They have a strong emphasis on gross margin and willingly share quarterly / yearly financial data in a "quarterly event," which after each of quarterly, they take the entire company out for a night of fun (cooking classes, golfing, etc.). It's a very young, vibrant environment and your coworkers are pretty much the coolest too.
Cons
This company has a knack of hiring some of the best and brightest minds, and then subsequently loosing them after a year or two. While I was at this company, tons of people came in and out. And the reason for that is they treat you VERY unfairly. There seems to be this implicit rule that you need to work 50+ hours a week and preferably more, which you're not rewarded for outside maybe a "thanks" from your manager. They pay you well below the average New York City salary. So if you've already built up your resume, then don't waste your time at this company. They'll suck the life out of you and pay you much less than you could be making elsewhere. At my time at SD, I worked long long hours, because I wanted to better myself and make sure the team excels. I was PROUD to be part of SD. I loved that team. But, it felt the feeling wasn't mutual; I was just a resource that they'd shift around and pump work/hours through. A lot of my resentment stems from the fact that they implicitly expect you to work outside office hours (which you don't get paid for obviously) and if you don't, you're scrutinized for it during daily stand up meetings in-front of your entire team. It's public shaming. That's all it is. And it's disgusting.
