I managed to get in a few laps last night with my G29 and usual settings of 7/4/10, 0 TC and ABS Default. I took away very positive vibes. I stuck with my Subaru WRX Gr. 4 and Gr. 3 cars since that is what I have been using in the Manufacturer Series and I am used to them. I've only done one Daily since the FIA seasons started.
Gr. 4 Dragon Trail - Gardens: Subtle differences here. I did some laps before the update and after. The tire model change is perceivable in that my old braking points, turn-in points and corner exit tecniques were no longer working, but the overall feel was similar. I was getting some feedback from the wheel under braking which never happened before. The Gr. 4 WRX felt like it powered out of the hairpin better with bias +5, and the on-throttle oversteer out of that corner was less snappy, more gradual. Off-throttle oversteer is much more pronounced and allows better correction in that four-apex sweeper near the end. I also did a couple laps with ABS on Weak instead of Default and I am pretty sure with some practice Weak will trump Default. Due to the lack of FFB for locking brakes I still don't think ABS Off is viable, but would have to test to confirm.
Gr. 3 Interlagos: The WRX Gr. 3 used to be a snap-oversteer festival, especially on tracks like Interlagos with tight corners, and it hates kerbs. Hitting the rumble strip at full throttle coming out of the Senna S upset the car as usual, however when the back end steps out a quick correction keeps me going. The slow middle section allows smoother and more consistent throttle modulation and if I give it too much juice coming out of those tight turns, the gradual loss of grip is easy to sense and correct. I had lots of moments in the 3rd and 4th gear turns where correcting understeer would unsettle the car and require some opposite lock to save it. Overall the behavior is much more realistic and intuitive. There is much more understeer but overall everything you want to do with the car is easily done with logical inputs.
I am a sim racer fan and prefer Assetto Corsa's driving model to GTS's but I do play pretty much all racing games, and I loved GTS for its Sport Mode despite the numb handling. With the new tire model it's still a long way off of AC but it is a massive improvement and has actually made driving enjoyable now. I am really positive about this update. It's a huge step forward for GTS.
Now let's hope PD doesn't go and pull a PD and go backwards with the physics in the next update. If they can improve it even more, great. If not, I would be happy if GTS stayed in this state physics-wise. It's definitely good enough for me and now I am actually looking forward to doing some laps in my classic road and race cars, something that before this update was reserved exclusively to Assetto Corsa and Project CARS 2 due to their superior handling models.