Try to imagine UOG Parklane 1 block have 32 floors, 14 units per floor;
average 3ppls in 1 family.. 14units x 3 = 42ppls; 42ppls x 32 floor = 1,344 ppls
For normal time maybe ok, but early morning n after work i think sure 'traffic jam' with the lift..
If emergency how? dun said emergency, let said if u stomachache also will wait until pengsan i think..
Then when wanna go out...wah..
Average 1 unit got 2 car ... so 4200unit @ 2car = 8400car.... wah

look at the access road.....

later sure jam
maintenance will be a problem for high density condo... people move in & out sooner or later few years down the road become pekeliling flat

I think the worst case you will get is how Setapak condo/ apartment areas are now.