I actually don't mind Import Tuner Challenge, but it's a bit dated. FWIW (ie not much) it's not a ripoff of NFS; it's a Japanese series called Shutokou Battle which began on the SNES, but is probably best known for the Dreamcast versions (Tokyo Highway Challenge). There's even an online version in Japan. The arcade game Maximum Tune is a quasi-spinoff (arguably the original game was based on the manga anyway, so it's tit-for-tat), and the Kaido Battle series - Kaido Racer over here - is also a spinoff (and a lot of fun, too).
Only real problem I have with Import Tuner Challenge is it's not as good as its predecessors. Tokyo Xtreme Racer on PS2 (Shutokou Battle 0) is more playable and the soundtrack is way better (IMO). There's a PSP version but it's pretty bad. On both the 360 and PSP versions it just seems too easy to get a BNR34 and upgrade it all the way. In all honesty, Kaido Racer 2 is the pinnacle of all the console versions. Comparing Maximum Tune to the home games isn't a fair comparison, though, unless you consider you can get Kaido Racer 2 for under $10!
OR IS IT?!?!?!