I would strongly recommend AGAINST flying out of Ellington Field (EFD) to get the extra 500 miles.

The reason is that the EFD flights are cancelled at the drop of a hat. I've had MANY problems because of the last minute cancellations out of EFD. And then you have the problem of trying to get from Ellington Field to IAH to catch your flight! The pilots that fly out of EFD are generally the newest and have the least experience.

In my opinion, its not worth the headache or extra segments...you're better off adding an extra connection to your flight elsewhere (ie CLE or EWR).