So, Bilstein recommend the 5100 series for up to 2" of lift, anything over that they say use 5125 or higher grade shocks. The KYB's would probably work fine for most 2" lifted R50's, I had the 5100 Bilsteins for about 6 years on mine & never had a problem, they are similar in length extended/compressed as the 5125's. My truck sat at 20"'s of shock length just on the ground so I needed at least 6" of travel or more, I have the AC kit rear springs with no spacers. The shock length isn't too big a deal as the sway bar is going to limit the travel anyway but when my rear axle is at full "droop" the sway bar & the shocks are at about 26" of travel & the sway bar is pretty much maxed out. The valve ratio on the 5125's is 225/70 so I should get a great, responsive ride in the rear. As for Kickinwing's question, I don't do any hard core flexing but I'd rather have too much flex available than too little, the KYB shocks would have been topping out too much for me & probably wouldn't last too long, if you can afford the Bilsteins I would go for it, I've never read a bad thing about them yet.