I'm just curious: Why not buy good Turbo games and good PC Engine games instead of going for a complete collection of either? Don't get me wrong, I don't mean to preach practicality and I understand that there's a certain undefinable element of joy that accompanies collection building, but this approach of buying all the US games and just a few PCE games seems like a bad idea to me for a couple of reasons.
For one thing, the price difference between the US and JP versions of certain games is especially absurd when you consider the types of games we're talking about. I mean, if you're looking for stuff like Might & Magic III or Cosmic Fantasy 2, then yeah, it makes sense to shell out some extra cash for the US versions. But why spend four times as much on the US versions of Cotton or Terraforming? Why not buy the JP versions (and have enough money left over for three other good games) instead of the overpriced US ones?
For another thing, there are so many great PCE CD games that they really are essential to making the most of one's "Turbo/PCE experience," and many of them aren't even expensive anymore. Why not ignore both the US AND the JP versions of mediocre Terraforming and buy Spriggan instead, since it's ten times better? Heck, you can buy an amazing epic like Kabuki Den for the same price as Takin' it to the Hoop these days. I know which one I'd go with.
Again, I understand the appeal of collecting, and I know that it's sometimes the most impractical things that bring us the most enjoyment. But this particular idea doesn't seem to lend to having the most fun possible with your system and making the best use of your cash.