As I recall from when I went through it 5 years or so ago, anyone who was chopped got their money back.
The foundation course (2 weeks) required a £500 bond, the remaining £5500 being due on commencement of the type rating with the selected (and agreed) airline. All £6000 was repaid during the 6 month line flying, in addition to significant tax free allowances.
It is unfortunate that it does exclude those individuals who cannot secure the bond. I found it extremely difficult to source the money, and was lucky to find it in time. However, anyone who suggests that places on the scheme are "bought" are mistaken or bitter. There is a very high demand on CTC to provide trainees, but the temptation to drop standards to cash-in is resisted and the selection proccess is maintained as one of the most thorough screening proceedures in the country. It's also worth remebering that they do chop people who have passed the selection but, for whatever reason, are deemed not to have met the required standard.
My experience was extremely favourable, though a close friend who I considered very worthy of their scheme was turned away. Personal experiences are subjective, but one cannot say that the product is poor, that places are bought, or suggest that the successful cadets are somehow undeserving of their new jet positions.