Ive used the Clark cheapo job from machine mart, i wouldnt recommend it unless you dont plan to use it - mine lastyed 2 months
Dont buy Snap-On air tools ever - in my experiance they are sh*t, a complete waste of time. My 3/8 drive impact gun (the new gay red magnesium one) is back at snap-on to be fixed again, i had it 3months and it decided it didnt want to do forwards so it went back, repaired and a week later it was doing it again. They have now had it for over 4months and "are waiting for parts". T*ssers

Everyone i know with snap-on air tools complains loudly and often about them
My Ingersol Rand on the other hand is a top peice of equipment - i have the 2135QTI, it is well made, light, powerful (1000lbs/ft or 1356Nm in reverse), and most importantly quiet like you wouldnt beleive. I would recommend them to anyone if your budget can stretch to it. You can find them for as little as £150ish although list is closer to £250. Do some research and you will find that this is more powerful than many 3/4 and some inch drive guns.
This tool has so far survived 18months of daily use and shows no wear or damage. It has been repeatedly drop off ramps and fallen off my toolbox and still works fine.
We have another at home, and a mate who is a truck mechanic also uses one and if it can survive falling off the top of a curtain-sider (he wrecks all tools

) then it will stand up to most abuse.
Use 10mm airline or larger (8mm will strangle any gun) and oil daily for a long service life
HTH
Lewis