> The American release remains about 95% the same as the Japanese original.  The control has been slightly tweaked (for the better), plus the manual and in game descriptions help quite a bit.  The main difference lies in the addition of at least 5 new cars: Audi TT 1.8T, Audi A4 2.8, Audi A6 2.7T, Dodge Viper GTS/R 2000 Concept and Ford Mustang SVT Cobra R (other new cars may be hidden).  A few new, more familiar sponsors can be seen as well.  The only other notable difference would be the reworked menu system (thankfully, it's better).  I definitely recommend the American over the Japanese version since it has something other than rice-burners...

     > As you know, Sega is well known for making great arcade racers with titles like Out Run (arcade, Genesis, etc.), Sega Rally 2 (arcade, Dreamcast), Virtua Racing (arcade, 32X, etc.), and Daytona (arcade, Saturn) to their credit.  This time Sega is going for realism all the way.  Actually, the only Sega racers in recent memory that incorporate realistic racing physics are AM2's F355 Challenge (arcade) and Sega GT.  Obviously, the main object in Sega GT is to win the plethora of races which are included.  The flow works like this: get a Driver's License (by racing); complete the Entry Class Official Races; complete the Entry Class Factory License; build an Entry Class car in the factory; complete the Special Entry Class Race; and so on through B, A, and SA Classes.  In between all that, you can enter Event Races to earn even more money, cars, body types, and sponsorship (BTW, you earn all that by completing Official Races too).
     > Importing isn't much of a problem.  Once you understand the types of cars (i.e. NA stock, Factory, 4WD, etc.), you'll have no problem accessing the various races.  Racing itself is a matter of acceleration, braking and steering (doh!) -- I know that's no problem.  Anyway, all the menu selections and game screens are in English, whereas the descriptions are in Japanese.

     > Simply excellent!  None of the courses is likely to yell out, "I'm pushing 70 zillion polygons per second", but the sheer detail, perspective, and lighting effects are enough to please the most hardened Sega nay-sayer.  It's worth noting that after putting many hours into Sega GT while completing all the Licenses, Official Races and Event Races, I've not even once encountered a hint of slowdown or frame drop (period).  The only thing that would look slow is YOU while I'm blowing by in a Dual Race.  Obviously, Sega put the time they had in development to good work.
     > The locales include seaside, mountains, hills, desert rock (dusk), city (night), and more.  Everything whisks by in unequaled realism -- enough to make some people queasy.  For speed, my favorite track is the seaside one because it's laid out just like Daytona.  For curves, my favorite track would have to be city night B (fwd) because I love that long straight away mixed in with the hairpin turns!
     > You get three views in the game: first person with rearview mirror, third person behind, and third person above/behind.  I prefer the above/behind view which gives me maximum sight distance and perspective.  Speaking of sight distance, it's almost unlimited -- if you can see things appearing while racing, then you're surely not concentrating on the race.
     > How about the cars?  They look just like their real life counterparts.  Take the lighting and mirror effects from Tokyo Xtreme Racing and up them a few more notches for Sega GT.  You'll have to really study the screen to see any polygons in the tremendous number of cars included here.  My favorite cars are the 4WD Nissan Skyline turbo (2 door) and the 4WD Mitsubishi GTO turbo - both are SA class.

     > This part is tricky.  If you've played Tokyo Xtreme Racing (TXR), then you'll know what to expect.  Sega GT's cars control like TXR's with an occasional tendency to fishtail too easily, which depends on the car you're using and the maneuver you're attempting.  Hopefully Sega will tweak this for the inevitable American debut of Sega GT -- or at least include a slider option to set the degree of ice and magnetism.  Driving with the Standard Pad or Racing Wheel works equally well.
     > In the Championship mode you can buy various new and used cars, build them from scratch, and win them too.  Upgrading them is a matter of money.  Usually a car can be upgraded to at least twice its stock performance through engine, exhaust, transmission, and weight reduction purchases.
     > In Single Race mode you're given the option of "grip" or "drift" control.  I'll just say this, anyone that can win a race using drift (I'd call it "POLISHED ICE") is certainly putting too many weeks into a single game.  I think the grip setting allows for plenty of drifting.  Other than that, you're given a choice of tracks and cars (including some really cool ones) for a single race in each class.
     > Overall the control is a mixed bag for my taste.  Sure, I know you can't take corners at 200 kph in a real car without losing control, but this is a game.  Some cars react better than others to component upgrades, which means some cars become very hard to control.  Specifically, they fishtail too easily (ice) or get pulled toward the walls (magnetism), or both!  Other cars actually improve with the identical upgrades -- go figure.  Still, once you've tweaked a well behaved car, you can have some serious racing fun at super high speeds!

     > Most of the music and jingles are very good.  You'll hear everything from easy listening (desert), to pop rock, to jazz, and more.  I mentioned the jingles because you'll hear a lot of them while traversing the complicated menu system.
     > The sound effects really shine through.  Everything from the engines to the sound of crashing metal is as real as it gets.  You can even hear the turbo whining at high RPMs!  Oh, and it's all clear as a bell on the uber-sound machine.

     > You can choose from Championship, Single Race, Time Attack, and Dual Race modes.  There's also a Replay Booth, download-able mini-game, and the ability to trade cars via VMS/VMU.  The Championship mode offers the Carrozzeria, which is a factory to build cars from scratch (not licensed, but look like Ferrari, Diablo, Porsche, Corvette, etc.).  In order to win many of the races you'll have to become proficient at upgrading and especially tuning your cars.  Of course, a lot of practice to learn the handling characteristics of your cars and the tracks themselves is necessary.  Control issues aside, the game drives one to keep playing with beat-able opponents, gorgeous locales, and tons of options...