I have attended courses of Czech in 3 different schools in Prague.
Regarding my experience with Noisis, I was mostly satisfied with the course, particularly given the price. The reason why I didn't continue was because the course itself didn't continue, which also happened when I was with CLT.
I attended an intensive course, and had two teachers. One just followed Czech Step by Step, and the class appeared less satisfied; with the other, we did other things and he (Simon) had a great rapport with us. He was our main teacher, and was really interested in our progress.
You can check on the internet what each school charges; however, from my experience, and from my friends, most Czech teachers follow the same methodology. That is, dull grammar exercises. So it might take you a while to find a teacher who understands what language is, and how it should be taught.
Simon made our course enjoyable, and my friends commented on my progress during this course. Compared to CLT, the course was noticeably cheaper, and therefore better value for money. However CLT and the Caledonian have better customer service.
Finally, the downside of Noisis is that they don't seem to support the teachers much - the Caledonian Czech Dept is much better in this regard.