My previous car was 2000 Maxima. Its suspension was similar to Altis. I replaced oem suspension with Koni shocks and H&R springs and both my wife and I drove it for 7 years. In 2012 I bought 2010 M35X for my wife but she said that the new M35X was unstable and difficult to drive...
Have you heard that if you choose Koni, you don't need to choose cars. I think "That IS True". Koni is really that good. The same as many high end shocks from Eroupe such as Bilstein, KW, Ohlins, etc.
I think the unibody of the car has to be stiff enough if you want to be benefit from stiffer suspension. My maxima was built in Japan and I think its unibody was quite stiff.