(– by Drizit #6240 –)
For airing down I got rid of my auto deflators and picked up the ARB deflator, Curry sells exactly the same one. It's faster and it's as accurate as you are. It does however require you to stand around with the bugs.
For airring up I have built one of those spyder hoses. you can build em for a bit less but mine ended up costing about $120 in parts from princess auto. I wouldn't plan on spending less then around $80 to build it. I also put a couple ball valves in to use it to air down.