I agree with Whopity, that it's pretty straight forward, and that 25 hours would be the reallistic number. I'm doing the FAA ME-IR as we speak, and I'm very happy about my choice at this time. By doing the FAA ME-IR you get so to speak the best of both worlds and it might take some of the pressure off your shoulders, doing your JAA ME-IR, since you'll have more multi engine experience. Beware though, and I'm sure you'll bump into this situation eventually, the CAA must according to the LASORS accept any conversion course approved by the CAA of the issuing state, but as an example it is known that the CTC Wings programme only accept UK CAA issued conversions, so it might be a bit tricky depending of your choice of career. If anyone outthere has experience doing converion courses, especially in Spain, I too would greatly appreciate some comments and advice. Best of luck!