I bought 3 Wordkeeper Economy Canvas Bible Covers in different colors/sizes for my family. They looked very nice when we received them, but 2 of them broke after a few months. These covers are inexpensive but not durable!
My NIV soft cover Study Bible is 5.75" x 8.5", and this medium cover fits like a glove. The material, workmanship, and appearance are all first rate. I have no idea why the description says "economy". Prior to this cover I had bought a different one through eBay which was also for "medium" Bibles up to 6x9 inches, but it was totally huge and ugly, not like the eBay photos, and got returned. The Christianbook cover is better quality, perfect fit, and half the price.