Pros
They offer unlimited PTO to their employees
Cons
Companies often go through similar patterns of growth. Innovation and excitement usually kick things off. Stagnation can then occur, initiated by lack of product fit to market needs. It's then that company culture can shift dramatically.
In the case of DNAnexus, they began struggling so much that they started to withhold payment to their employees - significant amounts (5 figures). They terminate employees for speaking up on the matter. It's clearly a sign of a sinking ship.