Do you all have favorite car that you use? I'll probably use the Dodge Rams for the classes they're in. The BMW for rally crosses. And probably the VW for T1 Raid.
We generally seem to gravitate towards the Rally and Raid classes as I'm host and I don't know of any car which is particularly dominant overall in those classes on the tracks we run (usually a medley of events not the 'correct' ones for the cars, though one car may be quickest it's not significantly so). Trophy trucks are a no-no unless we're private as the Toyota Stadium dominates, Trailblazers is dominated by the Dallenbach and Rallycross the RS200. Saying that, I'm not sure exactly how things stack up in Stock Baja and Buggies, I will investigate now.
Edit:
As for my favourites and a little bit about the quicker cars or so I believe. I'm pretty sure on most of my comments bar Buggies and Stock Baja I have used leaderboard research as I've never raced them heavily.
Rally
Personal Favourites: Escort or Group N Impreza
Fastest: The Escort, Group N, 350Z and Evo X are probably top 4 overall but there's not a huge gap. That said the Evo X is definately one of, if not the easiest to drive quickly which makes it popular amongst many players.
Rallycross
Personal Favourites: Metro 6R4 or Ford RS200
Fastest: RS200 without a doubt seems fastest and by a fair gap
Trailblazer
Personal Favourite: Solstice
Fastest: Dallenbach by a large gap and it's easy to drive which is why I don't use it
Stock Baja
Personal Favourite: Dodge Power Wagon
Fastest: Research suggests the Ridgeline may be quickest here but not significantly so, not personally tested many of them enough to confirm
Raid T1
Personal Favourites: Bowler or Hummer
Fastest: Not to sure, the Hummer seems popular on the leaderboard but I don't think the gap is significant enough to call it overpowered like the RS200 or Dallenbach in particular.
Trophy Trucks
Personal Favourite: Silverado CK-1500
Fastest: Toyota Stadium truck without a doubt and again is easy to drive.
Buggies
Personal Favourite: Dejong MXR
Fastest: Though not tried many of them much, the PRC-1 looks dominant on the leaderboards though again might not be significant.