Hi, I have upgraded my Sam² from 170 to 180mm with debon air spring.
main reason was for geometry and to get rid of the spacers.
frankly spoken: it does not make much difference (for what I do with the bike). maybe a little more stable on higher speed.
debon air kit itself is fine, from my subjective point, the fork get a little more sensitive.
(sorry for bad english, it's not my native language)
Hope this helps