I was really lazy to go into detail but here i go and please bear in mind, this is my PERSONAL opinion with several assumptions i make along the way.
I am comparing the the W204 C230 Avantgarde to the E90 325i and E60 525i. Avantgarde, sport versions aside, its just a matter of different kit, different interior spec levels and maybe most to most, a different spring set for different spring rates. Doesnt fool anybody into thinking the car is "sportier".
>> When u want to compare apple to apple C230 Avant must be compared with E90 Sport since both are sport tuned same price range. Sport seats, sport tuned suspensions, and aerodynamics do make a lot of different. Obviously a sport car is not really a sport car if the ride is soft and not connected to the road.
But anyhow, apples to apples first.
Looks: I would definitely have to give my vote to the more modern look of the W204 C-class. The E90, even post-facelift looks somewhat aged next to the C-Class. The muscular lines of the car and the sweeping shoulder is very very nice next to the not really changed E90 and it makes the E90 look aged.
>> This is subjective. I loved the C class looks to, but the image of "uncle businessman" still haunted this brand...maybe some aggresive aftermarket bodykit will eliminate the stigma
If you are planning to modify, have a look at the AMG kits out there and compare that with the E90 M3 4 door look. I think Mercedes wins this one in my opinion.
Some people doesn;t really care of becoming a wannabes....i'll just stick to BMW performance kit/parts the most
Driving: Here is where the E60 comes in. I dont own a E90 but i own an E60 525i Sports and the W204 C230 Avantgarde so thats why i use the E60 as a comparison.
Comfort levels in the C230 are much better than in the E60 in terms of the suspensions' characteristics, rebound rate etc. Less unsettling over bumps on the highway.
U want comfort spongy feel, get a camry, there is a reason why they're called sport sedan...its supposed to be connected between driver and road
NVH - Noise is slightly more in the C230. Maybe less sound insulation than the premium E60 but i cant say over the E90. Vibration is more in the E60 with a more communicative steering so i can assume this is the same for the E90. Harshness also worst on the BMW.
All in all, as the E60 is a more premium car over the E90, its expected to fare better than the C-Class in NVH and comfort levels etc but still the C-class feels much better. I can safely say this after hopping out of the BMW, driving the C and back into the BMW which i do quite often depending on which has more fuel.
Depends on what feel u are looking for? comfort, low noise, low vibration - u won;t get this on any sport car be it F430 Ferrari
Sporty characteristics: I think that the C-Class strikes a better compromise between comfort/drivability and handling characteristics.
>>>> Try the AMG version and get back to us on how the ride quality on that one
I think that over some surfaces in Malaysia, the E60 is too harsh and too bumpy/noisy etc etc (can you imagine the E90 then?) and i would rather have less of that communicative steering and awesome handling in return for abit of comfort and less teeth gritting everytime i go over uneven surfaces and tramlining.
I've driven both and i loved the feel of the E90 sport very communicative...the C class has a good handling too, but still not that sporty imho. How can you judge the E90 without test driven it and compare it with you e60 just because u think the 5 series is superior? hmmm for the same budget ie 310k i can top up a few more grand for the 523 model but i stick to the 325 sport because of the driving feel...
In terms of the interior, you only need to sit in both cars and make your decision. I know mine is with the Merc.
That is because u compare with the non i drive version which is 40k cheaper than the c230 avantgard...get into the 325 sport the idrive will blow the merc away
Dont get me wrong, i love my BMW for all that she is but i think the Merc strikes a brilliant compromise.
i can;t live without my idrive
After all, im not driving on the edge everyday. In fact im most often stuck in jams which is where the merc will excel.
I second that
Glad to be of assistance with my humble 2c.