Right. I'm currently at OATS, am a self-sponsored student, and paid 42K when the NVQ discount was still available last year.
I have found no fault with either the groundschool or flying instruction, the only problem being with the availability of aircraft at times, which I'm sure occurs at all flying schools at some time or another.
I would imagine the fact that BM, BA & Aer Lingus send their students here is proof of the quality of instruction. Oh, and don't forget the 12 students who were interviewd by British European and were all given a job, and the quote by one man from the airline "I only wish we'd started taking students from here before now".
Yes, I probably am biased towards OATS because I go here, but I doubt anyone who says they aren't biased to the school they attend.
In then end, it's best to visit all the schools and make up your own mind.