After three days...
... I "finally" unlocked everything.
It was kind of a bummer that some of the racers were unlocked after beating all the races - honestly, I hoped there would be more challenges for them, since they kicked my ass throughout the game.
This was just as fun as the last, and a wee bit more challenging. What the hell am I saying; this game started to piss me off it got so hard. It was good though - I think a game that doesn't challenge you or frustrate you to tears sometimes probably isn't that entertaining of a game.
Critique`? I 'spose there were a few minor glitches; such as CPU rider's floating in the air as they rode, or times when the would explode into birds for no apparent reason.
Also - as previously stated - I really would have liked to have some added challenges after the final base. There really wasn't any reason to play with the final bikers other than to gain money to max out the few remaining points I didn't buy.
All in all, I loved the game. Kept me entertained for a few days, and the character bios were... interesting to say the least. Sorry for the novel-of-a-review, but keep up the good work. It's games like these that keep me playing flash games.