The CJ4 has got the 680 Wing, its very good. It'll do 0.8 and Ive seen Vrefs as low as 92knts, no slats, no fences.
On my 680 initial I was lucky to have the Aero Chief in Waiting of cessna on my groundschool, they were very pleased with the wing and planned to use on a number of projects.
Theres no gains to be had with winglets on that wing, its efficient enough so that any gains made would be lost with the additional weight