I think the work environment lends itself well to people who require very little oversight. If you are expecting a lot of direction, the forget about it. Also, if you really crave to become someone's manager, that doesn't really fit in well here either. These aren't cons in my mind, but they might be to someone else.
The 401k matching is average, or maybe slightly below average, but all the other benefits much more than make up for the difference, e.g. with the employee stock plan.