Sew & Quilt Expos
 

Where is the largest and best sewing/quilt show in the U.S.

I don't know of any sewing expo but I think the largest is one in Houston in the fall. I know Quilt Market is for the people in the quilting business but I don't remember what the show following Market is called.

I would have to say Houston is probably the largest but best is subject to opinion http://www.quilts.com/quilt-festival-houston.html. Paducah is probably a very close second. After that any of the AQS quilt week events are fun and there is usually one held within driving distance for anyone in the country.
Then there are MQX, Road to California, Sisters outdoor quilt show, The Mancuso Quiltfest events. there are so many.

Puyallup WA in Feburary

Madison, WI has a very large Quilt Expo in September