Now, as anyone who has read or listened to me before, I have said Gran Turismo is a brilliant racer, but GT5 is bland to bad everywhere else. Now that I've essentially finished the Racing Gamers checklist with Forza (yes I bought a 360), I feel that, after some consideration, I can bring some perspective to the genre. I'll do this by looking at the series as a whole, not one game.
Gran Turismo series: The racing itself has always been the core focus at Polyphony Digital, and it has always been the biggest draw, even if getting there can be tedious as anything. So it's not easy to navigate, not is it the best looking, but it hasn't been called the 'Real Driving Simulator' for nothing. To my mind, GT is, maybe predictably, a purpose built racer like a Formula car or a Le Mans Prototype, maybe not the best looking machine, but it will mop the floor with any other competition.
Forza Motorsport series: Now, while I haven't played long, I have a good grasp on the feel of the games. I played 1 years ago, and picked up 2, 3, and Horizon recently to go with the new 360. Remarkably, some things don't change, like the interest levels. While they are fun, the fun is front-loaded in the games, being around the slower street cars. As you go faster, any unique attributes kinda fade away, especially if you turn off assist. The Performance Index is a nice idea, but it doesn't mean much as I can summarize level B and up as follows: Front-drive= spearing the wall, Rear-drive= spinning into the wall, All-drive= slapping the wall. No, Forza is more about the spectacle, and Horizon, the best of the series so far, is a shining example of this. The generalizations above are enhanced, and the festival setting and gorgeous-well-everything is the focus. If GT is the LMP car, Forza is the top-of-the-line Supercar, stunning to look at, but can never reach it's full potential on the track.
Midnight Club series: Oh boy, this one is hard and easy at the same time. Hard because it is, like the scene it was based on, dead. easy because it was hard to master, made no sense half the time or more, destroyed great cars for looks, and wasn't the best at the subject matter anyway. MC is like the tuners it represented, more flash than bang.
Need for Speed series: Hurk! So many games. So many failures! This one has been giving me fits, but I have it now. The series has gone from one side of the gameplay board to the other a few times, each trip producing at least one decent game. Everyone has a favorite, but everyone has different tastes, thats why NFS is the two-door roadster of racing games, some great ones and some horrid ones.
Burnout series: Rental car. Moving on.
Codemasters racing games: As one goes, the others follow. I got my hands on TOCA 1 I believe, and is it awful. Control was apparently an afterthought, but a 3DO was involved, I'll brush it away. Instead, there's Jarrett and Labonte (TOCA 3 I think), and the Race Driver games, culminating in the upcoming GRID 2(which I won't be buying thanks to thier greed.) which have to date been either bloody wonderful or bloody awful depending on who you talk to, but all have been flawed to a point, either by repetition, length, or overambition. Codies tarmac games rank as muscle cars, great fun but limited by itself.
Codemasters rally games: The other. Oddly, I can say the same thing as above from J&L on, but the rally focus can take away from some faults. As Dirt 4 comes closer, I think long and hard on the entire entity, and deduce the equal. Codies rally games are the RWD rally cars, great fun(again) but limited, waiting to be overtaken.
Mario Kart series: NO.