Ok, I have had a lot of P.Ms about the process so here is some info.
ICAO IR holders can get an hours reduction from the UK CAA only. The rating itself can be done at any JAA FTO anywhere in Europe; however you must be firstly a CAA license holder. In simple language if you don't have a CAA book you would have to do a full 55 hour modular course.
The school I dealt with in Spain knew all about 170a tests and all the paperwork. Once this is complete with the corresponding paperwork from the examiner you send it all off to the UK CAA at Gatwick, they put the rating on your licensee with a CAA stamp. It does not say where, or what country it was completed, they are the issuing authority. The Civil Aviation authority of the country you do the rating in is only supervising the training.
As for the schools. I had an FAA IR and, for a student, a solid block of IFR flying in the US. Despite the contempt that the training establishments on this side of the pond hold them in, they were bloody hard tests especially the Oral. I didn't feel that I wanted to jump through the same hoops again in the UK, especially in terms of expense. I spent ~3,500GBP converting in Spain, I was told I would expect to pay up to 10,000 GBP in the UK as I would not pass in the minimum 15hrs.
As to the standard? Well I can only talk of the small school I dealt with. I certainly would not have wanted to do the initial rating there. The standards were poor; students were rarely put under the hood or similar devices. Navaids were in short supply often a remote navaid was used with a modified approach plate to suit. Practice Approaches at major airfields were difficult to get as the military controllers were on an unofficial go slow.
Like I said earlier, for me it was the path of least resistance, I got the rating converted from my FAA in 8 days, at a considerably reduced price.
As for being asked where your rating was completed, I can't comment. I am now flying with a major European airline and at interview they were not interested, just as long as I had a license number for them to fill in on their form.
Also interesting to note that I did my CPL in the US and my IR in Spain, yet I have a CAA license and have never flown in UK airspace.....
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