Hi all,
Within the last few months of racing the TRB1 cars a lot, the balance is very different from what the robots are saying, at least in my opinion.
Please note that I was using default setups for all seven cars, and that I always drive against the SIMPLIX-TRB1 bots.
 
Top tier (Best of the best) :
car1-trb1 : Racing against bots like SIMPLIX or USR, you would think that a car with high speed is better suited to exactly that... wrong. On mid-speed tracks like e-track-6 or e-road, this car seems to be the only one (besides car2) to be fast enough to keep up with leading cars. Since it has a high amount of power at the top-end, long straights are no problem. Sadly, this can't be said for the lower-end of the powerband for not only this car but all except car5. Only weakness are on the really high-speed ovals, where it's bad low-end will take away any chances to stay with any rivals at the start. For some odd reason, the same can't be said for the TRB1s driven by SIMPLIX.
Setup advice: Shorten the gears or diff ratio a bit to make acceleration slightly better. Lower BOTH front and rear wings if more high-end acceleration is needed, because if you adjust only the rear, the car may become unstable.
 
Mid-high tier (Has a fighting chance)
car5-trb1 : What!? The "crappiest" car for robots is actually a good one for human pilots!? But hold your breath: The powerband of this car is amazing. The top-end will not be so awesome as car1's but I think the low-end acceleration makes up for this big time, even moreso when starting behind on high-speed tracks. The poor high-end power can easily be made up with good drafting/slipstreaming, anyways. Oversteering is a big problem on real low speed courses like Aalborg, ironic considering this track should be car5's home course. Actually though, even though this car is really slippery, the slides can be saved fairly easily.
Setup advice: Stretch out the first gear to make the most out of the car's acceleration and stiffen the front end suspension or ARBs to combat the oversteer, but do not overdo it. Smooth application of the throttle is needed here to prevent slides.
 
car2-trb1 : Car7 on a sugar rush. It's as easy to drive as car7 but a bit more prone to bottoming out. Unlike a good Porsche clone however the default setup doesn't really oversteer all that much, something I loved doing in the Porsche GT3-RS in GTR2 :( At speeds over 265 km/h, the power practically dies.
Setup advice: The setup of this car is really exaggerated understeer. Knocking a few degrees off the rear wing will work wonders here, and raising the car a few mm doesn't hurt either. Use stiffer ARBs to change the handling. Stretch the first and second gears as much as you can, and shorten the diff ratio or the top gears a bit.
 
car4-trb1 : Car2's American cousin. Fun fact: there is actually less than 50% weight on the front of the real-life counterpart to car4. ;) Facts aside, this car is kind of like car5, but it's not as slippery. As with most of the TRB1 cars, the car seems to understeer quite a bit. A good all-round car for any course, just careful of the car's underbody scraping the ground.
Setup Advice: Raise the ride height on all corners, knock off a degree or two on the rear wing, and
 
Mid-low tier (Needs to be driven like crazy to win)
car6-trb1 : Don't judge a book by it's cover: this is probably one of the sexiest cars in all of the TRB1 carset. But racing ain't about being sexy. Somewhat like car2, this car also suffers quite a bit from being snappy. It occurs a lot with a light amount of brakes and no throttle, which can be a good or a bad thing, depending on the car setup. One thing's for sure: the top-end of this car is rubbish. A new aero package would do wonders on this car's performance. And it would be even sexier.
Setup advice: You can use the oversteer to a big advantage on this car, moving the brake bias a *little* bit backward can work wonders. Knock a degree or two off the rear wing if you wish. Increase the diff ratio and shorten the gears.
 
car7-trb1 : Bernhard's dream racer isn't exactly the best one, and since most people don't drive like USR, the low power makes me cringe. The powerband is almost as good as car5's, but almost is not good enough, especally when the output of that almost is more like not even close :/ Really, the only thing going for it is that it's the easiest to drive of all the cars, and you can save many bad curves in this car.
Setup advice: Knock off as much off the wings as you can do make the acceleration better until you can handle no more. This car needs every little bit of drag gone. Slight shortening on the 6th gear wouldn't go amiss, either.
 
Bottom tier (Needs a miracle):
car3-trb1 : A top car in the initial TRB1 release, this car is now just a shadow of it's former self. The rear end seems to love losing it, and the tyres feel narrow even though I know they're not. The power is almost as low as car7's and the powerband stinks horrifically. I guess this car could be a nice D1GP car, but personally car5 does a better job at impressing the judges :/
Setup advice: This car will have bad rear-end grip no matter what, you should lower the front wing quite a bit and shorten the gear/diff ratios. Softer suspension (3500 is a good start) wouldn't be such a bad idea, either...