Bought this game back in Nov '04, US $30, for a long time it appeared as if I was the only one playing this. I stopped playing it when I got to RS LVL 10 with 5 Enthu points, using the RUF & Skyline R34 R-S v-spec.
The physics in this game was far ahead of it's time. I think that because of the realism, it turned the fun factor off for most people who tried it. For me it was a dream come true. A game with such a wonderful re-creation of driving physics.
It takes a much longer time to master this, than any other driving sim out there, even in today's standards. Only wish it were spec'd for widescreen 16:3 aspect ratio.
And, yes, it is a very intimidating game. Especially Dragon Range, uphill or down.