I was told by AC that the 5.14 gears will correct the speed-o with 34in. tires. That will work great for anyone using 33in or tall 32in tires. The transfercase gears will only affect 4-low and not help with normal onroad driving with bigger tires.
If you wheel a lot then go with the transfercase gears (your clutch will thank you). If you run huge tires but don't see 4-low to much then go with the differental regearing.