The AA kit is more popular, especially when bought with the CV shaft from Tom Woods. I don't think there is enough difference to split hairs, though.
Dora at www.adventure4wd.com has the "Custom Built Premium Long Travel Splined Tom Wood driveshaft and Heavy Duty Advance Adapters slip yoke eliminator kit for NP 231 transfer case - the most trusted combination in the market! " for only $510 & FREE SHIPPING.
OK I ended up buying the JB SYE last night on eBAy. Great deal $245 shiped and new. But thanks for the help. WHere do you recommend me getting the CV d shaft?