Note: Negative toe might still work in the qualifying environment. But all my setups will for now utilize positive or only slightly negative toe as I expect it to be the more sustainable solution.

The new Merc (looks like the old, but had major updates to front suspension and aero map). It relies a lot on rake to extract performance, as rake will increase the front downforce quite drastically - in turn this makes the car a little pitch sensitive on entry, especially in the fast corners. It can fit almost any kerb and also has no issues driving through the grass without bottoming out as the rear usually sits very high. Torque wise its as good as ever: Endless, while not even needing a lot of fuel. It's somewhat of an inverted Porsche. Heavy engine in the front, fuel in the back, which of course is missing in Qualifying, so the balance there is harder to achieve than in race trim. However toe and camber together with the right spring and rear squat can get something useful out of it, even if not perfect. In the race its much more balanced and you are much less front limited as you were in the previous patch. Initially it over-rotated coming form the Q set and I had to help the rear a bit to remain in its place. Beware of overdriving. Even in 23C the tires go near 100C and there will be a rather sharp change of grip once you exceed it. Maybe increase pressures further and open the ducts fully to keep them lower. This also means over-driving can come very costly. Once the tire becomes too warm, it will be hard to recover. You will have to take out pace until the temp drops and then drive normal again.

Brands Hatch
Braking in Q is trickier than in race trim, due to the missing weight in the back. The setup changes quite a bit from Q to Race here on Brands.
Especially in the race it feels very balanced and despite the wear difference, it remained stable as far as I got into the stint. The race set definitely starts on the understeery side, but it will certainly become more oversteery as the weight balance changes and the rear tires outwear the fronts - also the increased rake will add downforce to the front as the tank empties.
Brands is special with its fast corners you always trail the brakes into. In Q the car is pitch sensitive, while in race its not. The tight and bumpy corners need a rather soft set and need to be dialed in for traction that remains stable despite the track irritations. Soft setups come with the issue of behavior changes with pitch - this has been muted mostly in the race with the stiffer springs, but will be more prominent in Q. 

Driving

• Shift early, like 7100-7200rpm max. It's just about when the lights start flashing
• Aim for late apexes and dont shy away from a short shift or staying in the higher gear option in the first place
• your brake is more than a means of deceleration, it also controls pitch and especially in Q this will be key to managing rotation on corner entry
• on throttle the car will keep rotating, dont just floor it as that might exaggerate it - take a close look at my throttle traces.
• dont steer too much, progress into it, be ready to steer neutral on exits.

Adjustments

• If too oversteery: Stiffer front spring, stiffer front roll bar, less rake. One click at a time.
• The brake bias is tricky. If it's too far forward the front will suddenly regain grip and the rear snaps. If too far back the rears might lock. Higher ABS here if you cannot handle it, but likely at a time loss. Clean trailing will pay off.
• higher preload can give more turn in stability, but will come with more nervous exits
• lowering front and adding rear camber might further stabilize the car (in race) 
• lowering the caster also gives more predictability
• Some drivers might like a car with less rake for better drivability. It does not seem to be too problematic to lower the wing in turn for 2-3mm lower rear ride height. Or vice versa, add rake and increase wing

Tire pressures
Aim for 26.4 or more. Lower pressures might feel better in a slow corner, but its harder to hit the right slip. Go for 26.7-26.9 for solid support from the tire without surprises. Here its aimed to have the fronts at higher pressures than the rear - they need the support while the rear needs to come around on throttle and allow a bit more flex in the tire. 

Lap times
Q fuel: 12L
R: 102L