which cold air intake seem to be the majority winner?

[Planohummer]

the volant seems to be made of a little bit sturdier materials, both will give you a pretty much equal boost in HP. Any increase you got in MPG is immediately offset by the joy of putting your foot into it repeatedly.
If your truck is a 2005 or newer you'll probably need to get the corresponding MAF upgrade with the cold air kit--the newer trucks don't respond too well to cold air intakes with the factory MAF, check engine light comes on and truck locks in 2nd gear.