I'm not talking about the spring or any of that the rear compresses so you're gonna want the valving stiff so that it sets down slowly.

if he's going to get conventional single adjustable rebound the only good option is to only put them in the front.
in the rear just get regular replacements. stiffer rebound in the rear is gonna do nothing for you. at least up front and they will help keep the front end from lifting as fast