For most applications the 4.7 is way more than enough, the main reason for even having duals is that the 4.7 is already too low and having the 2.28 balances things out for general offroad travel while the 4.7 is there for crawling. When I had duals in my Samurai (Klune-V) I would have my front stock case in high 4wd most of the time and the Klune in low and very rarely would put the front in low.
