Welcome on MR!
Someone referred me to Swap Shop once for custom exhaust work (pair of resonators) I was thinking about getting done on my 135i. I was well served by polite and knowledgeable guys, who took the time to answer my questions, and describe their approach. I was pleasantly surprised that they would care about work on Euro cars.
Anyhow, lots of expertise at that place, and they are heavily involved with rally racing...
I would not hesitate to deal with them, or the other main Subaru tuner in Lachute ...
Their reputation speaks for themselves ...