We do have the RK's 2.5" on all locations. I'm good with the ride and the handling. It's a bit stiff on the front end, but I think it would be ok if I did not have the Michelin XZE*. The "*" XZE's have stiffer sidewalls. I went with these primarily for the rear, just in case we 'kissed' a curb while doing tight turns over the 7 years of planned usage. We're at year five now, and when we replace them I'll again go with he XZE* on the rear and tag, but probably the XRV on there front, and if I have room, bump it up from 12R.
OK, back to shocks. I feel it would be worth a call to Koni, to ask them if they have a "99" shock for your application. Many of the Western RV Alpine owners are very a happy with the "99".
Best of luck to you,
Roo II is our 04 Country Coach Allure 40'
OnDRoad for The JRNY! Enjoy life...