Throughout all of the series, the cars have been organised according to some common defining feature: 4WD class cars are obviously 4WD, FWD cars are obviously FWD, and so on.
DiRT 2 abolished this practice by instead seperating the cars into their respective event class (rally, rallycross, Raid T1 etc.). However, cars could be upgraded or downgraded into Rookie, Pro or All-Star classes.
DiRT 3 seperated the cars into their eras; such as '60s, '70s, '80s and so on.
DiRT Showdown utilises an upgrade system, meaning players take all cars (with the exception of the Gymkhana cars) from D class to A class.
DiRT Rally is similar to 3, with the rally cars separated according to their eras (Except for F2 Kit Cars and R4 Rally, Group B cars are separated into both AWD and RWD). The hillclimb cars and rallycross supercars are in their own catagory.
DiRT Rally 2.0 newer cars are fitted into similar categories as in the previous game, but older cars are now divided into H1, H2 (FWD), H2 (RWD) and H3 categories. These categories mostly follow the decades that the cars came from, but are aimed to be more balanced, with more powerful cars from '60s and '70s, like Alpine, 240Z and Stratos now competing against newer cars.
Contested Sequel: Many people who sank tons of hours on DiRT Rally see 4 as a step-down compared to its predecessor in terms of handling. The random stage generator has also caught some flak due to recycling stage sections. However, that doesn't mean the game doesn't have its fans, who appreciate the Sequel Difficulty Drop to make the game more accessible to beginners and casual players, and crew management.
DiRT 5 was seen as a massive step-down despite being a Sequel Escalation possibly because the thing is basically Need for SpeedProstreet with dirt track, with shifting emphasis from lifelike rally events to a fictional dirt-track racing league and most of the new cars are mostly fictional rally-modded variant of street and sports cars.
Renault Alpine in DiRT Rally is an RWD car in the 1960s class that beats most 1970s cars in terms of handling as well as performance and driving Alpine is often mockingly described as "easy mode" by players for this reason. Indeed, it's not surprising that in DiRT Rally 2.0, Alpine has been moved to the H2 (RWD) class (made up of the previous game's 1970s cars), where it replaces Lancia Stratos, that is now competing against cars from the previous game's 1980s class in the H3 (RWD) class.
Also from DiRT Rally, Peugeot 205 Turbo 16 Evo 2 is very much this trope in Difficult, but Awesome form. While it's easily the hardest 4WD car in the game to handle (being the most powerful rally car in the game and all), it wipes the floor with the rest of Group B cars once you learn to use it properly.
Scrappy Mechanic: The asphalt physics on Rally 1 & 2 are a source of contention with fans, with critics charging that they are too 'floaty' and similar to the loose surface physics, though defenders point out that rally cars handle more differently on asphalt than those used to circuit racing are expecting.
Tear Jerker: Beating the Colin McRae challenge in DiRT 2 treats the player to a short tribute to Colin's rally career.
The Monte-Carlo Rally, DLC in DIRT 3. To elaborate: Most stages in the game are wide enough to fit at least two cars side by side. This rally has sections where only one car can fit, and it's a tight squeeze. It's not much easier in DIRT Rally.
In DiRT Rally, pretty much every single track can become this. Justified, though, being a Nintendo Hard game at its core. In 2.0, however, Argentina has received the most fear from the players, being a rally full of tight courses with massive rocks and boulders scattered throughout the sides of the road. In particular is one particular sharp left onto a tight bridge on the edge of a deep ravine that is a guaranteed 'Terminal Damage' if missed at almost any speed.The very tight hairpins mean that mastery of tricky handbrake turns is a must. Then there are some faster sections dropped in that mean the gearing has to have a taller top gear to avoid buzzing the rev limiter.
Sprint races in DiRT 5. You drive an Awesome, but Impractical Sprint Car. Has lots of horsepower, prone to wheelie, impossible to control, even for some experts. It didn't even help that the game has Rubber-Band A.I., even if it's set on "Very Easy" difficulty.
DiRT Showdown is viewed as such by a number of players who are understandably fed up with the "dudebro" attitude espoused by the previous games. It took out the traditional rally modes and replaced it with demolition derbies involving Fauxrrari cars.
Same went for DiRT 4 whose handling model is a single point of contention amongst sim racing fans.
Surprise Difficulty: With Rally 2, enthusiasts know (and the casual players may have heard) that Finland is very fast, Argentina narrow, Sweden snowy, and Greece very rough. But the wide open spaces of Australia are filled with hazards; fences, off-camber tightening turns, sudden junctions, narrow ridges, surface transitions and narrow gates. Scotland, too might naturally seem like Wales, but it is often much faster, with sections to rival Finland, only narrower. The Col du Turini on the Monte Carlo might initially seem like a colder Spain... until the snow and ice fill the road. It is held in January after all.
Win Back the Crowd: How many of the fans view DiRT 3 and DiRT Rally, especially after their dissatisfaction over Codemasters pushing for too many arcade-y or gimmicky elements in DiRT 2 and DiRT Showdown.