Well, I'll speak up for the International Quilt Festival in Houston in October.
Houston's show is the "original" big show, has been around for decades and is spectacularly done. Everything is in ONE venue (unlike Paducah's), indoors (unlike Oregon's), has too many hotels and restaurants to name, and shuttle buses to many of the lodgings.
It is truly international, you will see many groups of Europeans, Asians, Australians, etc., there.
Classes, the show, the vendors and food are all in the George Brown Convention Center, covering three floors, and a block long; it's huge!
Go in the morning and stay all day, for at least three days to even see it all, much less take classes.
There are elevators, benches upstairs for resting, meeting locations in which to regroup, package check-in, mailing station, and many other amenities to support the 50-60,000 people who visit this show each year.
There are interesting restaurants within walking distance of the venue also.
Houston has wonderful museum, shops, theater, clubs and nightlife. You will get a good taste of Texas here, too, also a chance to visit several local quilt shops -- though they will represented among the hundreds of vendors on the show floor, too.
Be sure to check out
http://www.quilts.com/home/index.php for ALL the information about this show.
Jan in VA