I am sure you would have done your research here before handing over any money so there is probably no point in doing it again. I wouldn't do anything based on the views of one person though - he or she could have had a bad experience and could be bad mouthing the school over something which might have been their fault.
A good school has experienced, knowledgeable instructors and good notes. The school should ideally have good links with the CAA (to facilitate discussion over dodgy questions etc.) and have an excellent database of feedback questions. Sometimes the questions are worded in a way that means it isn't completely clear what they are looking for so a good school will be aware of traps like this and will usually have a view (the correct view) on how they should be answered. Try to talk to as many people as possible who have been through this school and get their views. If you do end up walking away don't worry. If they do hold on to your deposit just think about how little that amount is compared to the thousands you're going to be spending. When you do your IR, you will be writing cheques for hundreds of pounds without even thinking about it
The facilities shouldn't be a huge issue. I used Oxford and the facilities were average to say the least. There was very little use made of computer learning in the classroom (this was 01-03 so could well have changed) and it was mainly "chalk and talk". There was one poor instructor, but the rest really knew their onions.
Good luck on your funding - let us know how you get on....