QUOTE(ESP156 @ Jun 7 2012, 01:17 AM)
I hv been driving m3 for few months and I feel this car is very well tuned toward comfort and handling as a stock car. the stock suspension feel very firm, the 17 inch wheels and the brakes feel very good on Malaysian road. My previous rides uses 215/45/17 too but was a nightmare when going thru potholes and yellow stripes. Thus I would say the comfort handling is not the entirely due to tires, but also the suspension design at work. I also have same issue with u, one road near my office is full of portholes too, but i have programmed myself to drive slow and carefully for this stretch, not because the car cannot handles it, but I am trying to minimize the wear and tear to drive shaft, the lower arms and related parts by going slow.
Back to tyes change, I find the rides comfort was is about to same after switching to 215/45,
If want to be peculiar i find the steering is receiving more feedbacks on road conditions than 205/50 settings,
Thus it can be perceived as it is more bumpier however the different to me is very minute, and i dont feel any sacrifices of comfort after 2 months of driving..
Otoh i find 215/45 handles better than 205/50 and when taking corner, if there is 215/50, that would be the best of both world.

bro thanks for your detailed input, very much welcome
def 215/45 has more grip and give more feedback compared to 205/50 due to wider contact area, but if you said the comfort level is not noticable between the two then i'm happy to use 215/45 again... 205/50 very rare laa
there's no 215/50 but we do have 225/45 which give us nearly same diameter as 205/50 but with wider tyre (2 mm more than 205)... i'm thinking to upgrade to this size but feared while comfort is improved, the drag also higher and thus affected the FC, but of coz grip also shall be better... sigh, don't know how to decide
for me the M3 is tuned towards handling and thus firmer suspension, but only on low speed bump the harshness felt... i noticed that when going through holes at high speed the comfort is good, better than my waja...

so my solution sometimes is just drive through the hole at more than 60km/h, but of coz not always la scared suspension rosak