Originally Posted by elCheapoDeluxe
My targus set cancels up to 16db. I can't say how it compares because Bose does not publish specs - a carryover from the fact that they don't publish specs for their speakers due to their poor midrange performance. I would strongly suspect that they are right around the 10db-12db camp.
Bose claims 30db.
I'm unfamiliar with the Targus phones you're referring to. However, NC phones need to be tested under conditions similar to where they'll be used. A kiosk in a mall is not going to present the same aural environment as an airplane in flight. The Bose do an amazing job of reducing the whoosh and roar of the noise generated by the engines and airstream.
The short of it: I wouldn't buy a set of headphones without listening to the competition. My requirements may vary from yours since I prefer use a seperate set of high-end headphones for non-NC use, but if NC capbility is your primary requirement then I don't think the QC2's are a no brainer.
I have compared NC phones, and find the Bose to be the clear leader, both in terms of cancellation and in terms of audio quality. You might want to try them in-flight. As I recall, Bose has a 30-day money back guarantee, no questions asked.