NCSU most people do pass their quals and they try hard to get everyone to pass their quals. You have to pass three quals, and have two tries to pass them. Apparently the professors look out for you and tell you whether or not they think you are prepared. I don't remember the exact percentage (probably because they didn't give us the exact percentage), but they said only a few people fail out.
The job placement is mostly in industry or national labs. They have a lot of connections with the local industry places and the nearby lab. Or they have a much bigger emphasis on placing people into industry. Tim Kelly places almost all of his students in industry, but they said that they also place people into academia positions as well.
I can't say much about the welcomingness of the faculty. We didn't get to interact with them as much as on other visits. They all presented on their research, but we didn't have that many one-on-one meetings with them. One of my friends goes there and he seems to like the faculty well enough.
The students are not competitive with each other at all.
They have a pretty strong emphasis on math bio as they see it is a growing field and want to do a lot of research in it.
Hope that was helpful! The visit was a while ago, so my details may be a bit shaky.
I also don't necessarily know about how big of a deal ranking is. One of the things I would recommend would be look at the job placement (http://www.math.ncsu.edu/grad/brochure/employment.php
) and compare it to the other school that you are looking at. All of these schools will emphasize their success stories, but it does give a sense of where people go to teach and work.
The school is also 50-50 men/women, which was just cool when visiting it and comparing it to the 80-20 at other schools.
Anyone else want to chime in?
EDIT: I just remembered: I also don't know how difficult it is to work with someone who you want to work with or if there are any faculty members that are more busy than other faculty members.