Wow, this triggers me to offer my opinion, but my opinion is rather scattered. You could go to SubaruOutback.org and spend hours of your life and come away fairly confused. I don’t have any experience with a gen 5 (such as 2015). For gen 4 (2010-2014), the yellow B6’s are waay too harsh, at least on my 2013 6 cyl model. My overall opinion of the KYB’s and the OEM ‘s (at least for Gen 3 & 4) are they wear out prematurely, and until then, their damping is just not great (too firm and too soft at the same time…how can that be???too much compression damping, not enough rebound???unless heavily loaded in back)). That said when I rode in a relatively new 2025 Outback XT, I was impressed, so somewhere in there, Subaru must have improved things. but I wish Bilstein USA would talk to their brethren in Japan, as some JDM Bilstein offerings for the older OB’s hit the nail on the head much better (well, racers may want even greater control at expense of even a modicum of comfort). When I “recently” spoke with Bistein tech about B4 and B6 (are both models available for Gen 5?), he said the B4’s were 100% like OEM, would offer no (absolutely zero) improvement over OEM, except not worn out. So I got the B6’s and can barely stand them except on ultra smooth asphalt…where they excel. So Bilstein needs to share some notes with their Japanese counterparts: build in a little plushness, but somehow also provide better control…even if it meant different springs too. I always joke when someone asks me about them, saying “Bilstein needs to make a B5 for the Outback…or go back to the drawing board: revalve the B4 for maybe 15% better control than OEM, with more refined rebound vs compression curves, and back off the B6 initial damping by 15%…or somehow soften the 1st 1-1.5” of travel firming up rapidly in low-speed damping beyond that. I think the 2 models would still be miles apart.
Another disclaimer: maybe the Michelin Defenders are contributing to my negative opinions…they are not new, but way to much tread left to consider ditching…maybe 40k left…when I don’t know if tires can make enough difference in this case (certain Pirelli’s supposedly have better ride without sacrificing handling / control…if you can believe tirerack reviews.).