Yes the AI in this game feels very amateurish. The people who programmed it clearly had no idea what they were doing as the rubber-banding seems to work exactly the opposite of how it does in most racing games. Normally the AI rubber-bands when you're in the lead in order to catch up to you and then eases up to give you a chance to reclaim your lead, whereas in this game the AI seems to slack off while you're in the lead and rubber-band if they manage to pass you. It's most noticeable in the first round of the Outlaw's Rush where the racer that is scripted to catch up to you about halfway through the race won't make much of an effort to pass you unless you open the door for him, but will pull away and become impossible to catch up with even by the best car in the game if you let him overtake.
However that's the one and only scenario I've encountered in the game that felt impossible to beat, one which doesn't even count really, since it's easily avoidable by not letting the racer pass you in the first place. The Hazard Company was easy to beat, both in the campaign and in free roam. I actually beat Holtzman three times in free roam, once with each protagonist. Off-road roaming racers are easy since they have weaker cars than the rest and drifting off-road takes little to no effort. The toughest roaming racer for me was probably De'Aaron, though I think that's mostly due to the track layout than anything else.
The most frustrating and difficult part of the game are easily Jessica's missions. Half of them revolve around escaping suicidal cops under a time limit. Yeah. Bad enough the hillbilly cops have zero regard for their lives or anyone else's and will gladly roll off a cliff with you at 240 M/h, but you have to take them on using the rubbish Runner cars which are basically just Race cars only heavier and with worse handling. Not only that but you have to do it under a strict (and apparently bugged) time limit, for some reason.
