Pros
Some offices seem nice and the partners there seem like decent people. Same for associates and staff. You'll probably have typical biglaw gripes, but nothing major. But if you find yourself in one office in particular, you are screwed.
Kontras
This criticism applies to one office in particular. There you may find a clique of partners whose behavior is atrocious. No joke is out of bounds: they ridicule gay persons, persons of peceived lower socio-economic status, disabled persons and single parents. Not abstractly, mind you, but directed at particular people (mostly hapless co-workers!). They do this behind the person's back, but in front of an audience of back-slapping sycophants. Some staff members also engage in this behavior (even openly partner-bashing to this clique), but not all.