VITZOOKER wrote:
so going down hill will be shit?
Yes but so will going up hill and on straight road, that includes taking up from lights and general driving will deteriate.....as long as your in high range.
as soon as you move that second lever into LOW range, the reduction gears will then take effect and reduce your drive ratio giving you extra awesomeness

it depends on the type of terrain that is driven, if a lot of sand driving will be done then reduction gearing is not advised unless you like to drive sand in 5th low range and reving the engine to redline. You could use high range but because of the 31's you will need to use a fair amount of clutch to start moving and will have less torque to keep you moving.
The gearing availible is really one sided. as in, it only really helps if rocky terrain is the predominant terrain because the reduction is so great (134% over standard to be exact), so this will mean that 5th low will be about the same as 1st in high.
hope this helps