Sam, a JAA 55 hour is a JAA 55 hour course wherever you do it. All schools are regularly inspected by the authorities (Aerofan were having their annual inspection while I was there). I admit that doing it in 3 weeks is tough but I already had an ICAO IR which I use in anger on a regular basis so for me it was no big deal.
That having been said, I met several students who were doing the IR from scratch and 3-4 weeks seemed about average. As I said before, the instruction was first rate, the whole course was done on aircraft, Madrid was fantastic fun and I completed on time and on budget. I can't say more than that really - it seems there are plenty of people on this forum who have had first hand experience of Aerofan and would agree with me. By the way, I didn't need to study mathematics as I did the ATPL writtens before I went.