Mount Saint Mary's is a private school, and that is why they are so expensive. The passing rate that you mention, is this for their ADN or BSN program? Mount Saint Mary's has both programs, and I believe that their passing rates are listed separately for each educational track.
One thing that you may want to consider is that MSM is only program in the area other than Cal State LA where you can go straight through and get your BSN. All of the other BSN programs in the LA area are continuation programs where you have to have your ADN first, so your final educational goal may be something to think about if the cost isn't too much of an issue. The other consideration may be what program you get accepted to. Competition for slots in nursing programs
has gotten absolutely insane.
Pasadena City College is a good school, the passing rates there certainly show that you can get a perfectly fine education at a public community college. I graduated from GCC, and under all of the rivalry, I always felt that the programs were pretty comparable.