I just received and installed my new Kyb rear shocks 344052 to replace the 343219 that I had put on a couple years ago. The 344052 look more robust with a bigger cylinder at same length, and I like that, even though I do not spend much time looking at the underside of the car!
In my case, height of the rear remained the same, but what a difference on heavily patched roads as we sometimes have here in Qc. I was happy with the 343216 that provided a smooth ride on most roads but what a better stability (and no more bung bung) when asphalt is damaged, with no sacrifice on the smoothness of the ride on better roads. I am very please with them - thanks to you folks for providing the info here.