Firstly, you need to understand the very important difference between SC and Associate at Booz.
Usually, when you get to SC level, after a year or so you are expected to disappear and do an MBA or a stint in industry.
When I was there as a C, I found this very unappealing because I wanted to settle down and take out a mortgage, yet there was this 'inevitable' point after a few years where I would basically face a period of great change and unheaval.
At Associate level, you will typically be working with 30 year olds that have just finished their MBA. Many of them will have had some prior industry experience. But be under no illusion: as an associate, you are the grunt that produces all the powerpoints for the project. I personally didn't much like working with the associates because so many of them worked such ridiculous hours. Also, I felt that for such highly qualified people, they sure took a very long time to produce even the most basic powerpoint decks. I guess they were just 'obsessed with quality'.
The senior associates were even more work-driven. There were some really good ones, but most of the SAs were REALLY hard workers. As in they lived and breathed the work. I really did like some of the SAs a lot.... but some of them were MEAN dudes. As in people who would do anything to get to Partner.
At principal level, again the same experience. Some really nice folk. All very comptent at this level. But they were all international types if you know what I mean - the sort of people that had never really settled down in any one country for more than a few years. It did make me wonder how they hold down a family life when moving all over the globe like that. Again, VERY VERY VERY hard workers. This was not a position for the faint hearted.
Then at Partner level, you generally had decent folk. Some of the senior partners were pretty mean and would say things in front of junior staff that would worry them. But I think those people have left now so the remaining ones are probably decent folk.
Not sure what salaries are but am guessing associate is about 65-70?