I am just going to jump in here and give my 2c worth without reading all the posts
Jap cars are very cheap to do up here in Australia now, parts are everywhere, in fact for the sellers it would seem as though there are too many parts. So I wouldn’t say they are more expensive than say a Ford XR6T, in fact I would suggest it is the other way around.
Personably, I feel Jap cars are much cheaper to pick up and are easier to mod. The R33 Skyline is a perfect example, or the R32 GTR. I wont give a GTR as an example as I don’t own one and I really have no idea how you can beat one without a GTR
For about $5000 anyone can build an R33 GTSt capable of around 250rwkws (After Ben Tunes it). With that kind of power there are few standard road cars that will even come close. I don’t think $5000 will get you much for a GenIII V8, but then I am not completely sure about this. I also have no idea how much a XR6T costs to mod but I assume its over $5000 to get a reasonable performance gain.
Anyway, at the end of the day we are comparing oranges to apples. All I know is at the time of purchasing my car (2002) it was either a 5.0L VN SS or an R33 GTSt Skyline, the option was simple.