i really like the game!
i am a bit of a turbo outrun aficionado. :)
i like the upgrade system, and the time mechanic is clever, but it's a little counterintuitive to have to hit down to see different upgraded parts in each category. i'm also not sure i get the weight reduction "upgrade". what does it do?
i also got a bit stuck: i was on 3rd stage and my lamborghini's engine kept blowing up and i couldn't complete the game, as i replaced it, but that one blew up too in pretty much the same spot in the same stage. i also noticed once your engine is blown, on the upgrade screen you can leave without fixing it/upgrading the engine, which ends your life immediately upon the start of the stage.
i was a little surprised the stages are a bit different from the original game, more generic. in the original as I am sure you know, each stage is a US city and the idea is you're progressing across the country.
a few small things that i love in the original game i'd like to see:
-the sega band that plays above the finish line
-your girlfriend leaving and going with the rival if you lose (and coming back if you win)
-barrels/cones that you can hit
-oil slicks that make you skid and (most importantly) can be lit on fire if you engage turbo while near them
oh yeah i LOVED the test drive inspired level :)
i think the game is super cool and i enjoyed it!