I think the CBI scarf is more authentic looking, but still more a copy of a souvenir item that would have been sent home.
Lots of units in the CBI had different Chinese made versions with their insignia/squadron patch on them. You see similar Japanese made scarfs from the Korean War as well....which I think were actually flown with more than the WW II ones.
I agree with the previous post, it you are going with something from the ETO, a piece of parachute silk or a plain white silk scarf is the most authentic.
As an FYI, there are nice original WW II era scarfs out there that were sold as souvenirs on US Air Bases that look like that 8th AAF one, but with the AAF winged star in it's place. Those are nice quality, and show up for $35 to $75.
Of the ones on eBay, for originality and something a pilot might have actually worn, I like these two better:
http://www.ebay.co.uk/itm/b1214-WW-2-US ... 500wt_1180
http://www.ebay.co.uk/itm/b1217-WW-2-US ... 500wt_1180
As an example, here is a link to one of the original WW II era scarfs I mentioned:
http://www.ebay.com/itm/US-AAF-WW2-ARMY ... 51a21c51c2