Pros
Excellence as an ethic type culture - very customer centric, master's level technical competence. Overall, a superlative organization to work for or do business with. The management was extremely attentive to the wants and needs of their clients and the staff. It's usually one or the other. I worked as temporary staff supplement, and would seriously consider going to work on a perm basis when and if that is possible.
Cons
None. The usual static involved with contracting and short term employment is at virtually non-existent levels here. Seriously, not sure how they manage it but I was paid on time, with none of the usual administrivia headaches. Working arrangements were very flexible.