All the Japanese cars I've had with leather seats held up well, but none of them had any leather aroma at all. Apparently, the Japanese don't like the smell of tanned leather, so whatever process they use doesn't have any odor. I really like the smell of leather - think old Jaguars - and finally found a good conditioner that smells great! And, actually, Zaino makes a great line of car care products. I've used many of them and have never been disappointed.
http://www.zainostore.com/product/Z-10.html
This is just a conditioner. For cleaning, I normally use good old Lexol.
Lexol conditioner works well, but I don't like the smell.
http://www.zainostore.com/product/Z-10.html

This is just a conditioner. For cleaning, I normally use good old Lexol.

Lexol conditioner works well, but I don't like the smell.