So far, my impressions of the PS3's main differences over the PS2's are:
1) Much more supple and comfortable over the PS2s. I doubted this and just rechecked the tyre pressures suspecting that Lim Tayar put in less pressure than what I usually run and the pressures are identical to what I ran on the PS2's. So there is a big improvement here. Car feels much less harsh on normal driving vs. the PS2.
2) Noise is about the same or perhaps slightly higher in low speeds, but seemingly less noisy at higher speeds vs. the PS2. Again its very close and not much difference between the 2. One thing I have to give the PS2's is that generally the tyre stays pretty consistent throughout its lifecycle. Not much deterioration once worn down in terms of noise levels
3) Drive on the PS3 is more interesting and fun over the PS2, mainly because of the feedback to the steering when driving it harder. E.g. under hard braking, you can feel the tyre biting the tarmac hard, giving you the more feedback and assurance in the drive. Just managed to pushed the car a little more today and its the same over hard higher speed bends, whereby the feedback the tyre gives back to the driver under load and G forces is much more inspiring and fun vs. the PS2. You can really feel the tyre biting the road and its never harsh and still "supple" in the way it does it. Hard to explain but the tyre feels GOOD!
4) The car understeers less vs. the PS2, but I suspect its due to my worn condition of the PS2 outer thread on the front tyres, and when new as well I don't remember it understeering as much as it did before the change. With fresh PS3's this this is back to what it should be.
5) Wet evaluation which is where the main difference is according to specs, but I don't think i'll be able to run a good comparo with the PS2's here, as I hardly push the car hard when its wet and pouring while I was on the PS2s. In fact I am super paranoid and careful when driving under heavy rains. So.... cannot give a good comparo in this area la.
6) Downsides of the PS3's is that it generally feels "heavier" vs. the worn PS2's. Hence I suspected that I was running lower pressures which wasn't the case. The more worn PS2's had more initial get up and go vs. my car now on the new rubbers. Can't really remember if this is the same feel from fresh PS2's but coming from more worn PS2s to fresh PS3s the difference is there. Hence my car feels slower now. Since the midnight drag E90 kaki has all graduated and are playing with tuned 3 ltr twin turbos now, its just as well now haha. My cucuking and drag days are over now hehe.
Bottom line, the main "improvements" are in comfort and feel. Ultimate grip in dry is somewhat similar but it gives the driver more feedback and feel through the steering now which enhances the driving pleasure. In day to day daily driving, the biggest difference between the PS3 over the PS2 is definitely in the comfort dept. When it rains and pours its supposed to be much improved, but I've yet to explore that so I'll leave it to the other BMWCM members with bigger kahunas running on the PS3's to report on that

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