With only a few hundred miles so far, it's still too early to tell, but so far I have not complaints about ESA. I had it on my previous bike for both front and rear, once I understood how it worked, it was the plushest suspension I've felt. The way my old bike worked is the rear received information from the front sensor, so it was able to cope with an upcoming bump. How does the 850GS ESA work, does it have a front sensor??