I have only looked at Qixo out of all of these. I tend to take a look at Expedia, Travelocity and the individual airline's websites for web fares. Lately, I have ended up purchasing tickets from the airlines themselves because I save on the transaction fee that the search engines charge. One site that I've been using a lot is ITA Software ( http://www.itasoftware.com/) Once at the site I then click on "looking for airfares?". This site is purely a search engine. You cannot purchase tickets from it, but it will tell you what the cheapest fare is (that is on the market at the moment). It also lets you check specific dates, weekend search and month-long search. But, remember, it may be sold out or unavailable. I find that it gives me a good basis on what I'm looking for. And there are always airlines that don't show up, for instance southwest and some of the other smaller airlines. I used to be a travel agent (many many years ago) and it reminds me of what it was like to look at the tariff for a city pair. With this information I know if I'm getting one of the better deals possible (at that point in time). You know airfare.... it's constantly changing!

Jenni in Chicago