AP seems to be the man most go for to be fair, he supplies and fits LINK ECU aswel. Peter Simmons also well regarded, he comes down to Joe Gallagher in Tipperary for remaps there too
AP is hard to get hold of but put a Link in my V3 and car is a rocket. A lot here would recommend AP as he has done fantastic work on so many cars here.
For mine he resolved so many issues and completely changed the car.
if youre around Galway, its much easier to call into AP to get an booking. You'll have one there and then rather than trying to get contact over the phone, but he's usually a few weeks sometimes months wait for a free slot
AP all the way. Only person that I would trust mapping my headache of a Subaru. He has remapped my car many times with different configurations and turbos etc and every time , its spot on.
Of note, he is also a Link and Haltech dealer if you need to get a new ecu. I am sure he offers a fitting service as well if you buy it from him etc. You will need to leave the car with him. I got a bunch of Haltech parts from him but Link is much easier to make it work on the Subarus. The new version of the Link Gx ecus are a lot more advanced now since the last version.