The Continental low fare guarantee is just B.S. It basically guarantees that the lowest fare you can find on continental.com is the lowest fare on you can find on continental.com.

There ain't nothin' that says that they can't offer lower fares on the same flights on the other reservation systems, but just using a different fare code.

Continental.com's inventory isn't the same as the other booking engines, often I can find more flight availability on the other systems.

It's useful to know that if you can find flights on the other systems, but not on co.com, you can call tech support, and they'll tell you that they have different inventory, but they can book you on the flights that are available on the other systems, and you still get the 100% EQM.