Although I never actually dealt with them yet, I told Agincourt Infiniti that I was planning to purchase in the US because I saved 10 Grand and they were okay with it (as much as they could be). The guy I spoke to actually wanted to use my spreadsheet of comparison costs to lobby infiniti to bring the prices down in Canada. He told me that it was no big deal to service a US car under warranty and that the only thing was that they would have to call Infiniti USA before starting the work. I had no trouble with my '05 G35x and don't anticipate any on my new 08 G35x, but at least they were friendly and didn't seem resentful about a US purchased car. After all, they want the warranty and service business, regardless of where you bought the car. On the other hand, I returned a leased 2005 G35x with no hassle to Alta Infiniti at 427 & 401 and they were great about the return, but seemed to frown on the US purchase idea. I think the sales guys always will be that way about buying your car from anyone but them.

For regular service I use my local mechanic who has serviced my cars for years. I get mobile 1 synthetic for $50 all in and no hassles. Regular synthetic blend for $35. I don't need an appointment and I'm out of there in less than half an hour. They also let me come into the shop (which they're not supposed to for insurance reasons) to see what they're doing and keep an eye on my car, which I love.