From: Northeast United States
I use two Case Logic 280 something CD cases, maybe 320, I forget. I also have one small Fellowes case to take to customer sites. The Fellowes will put marks on the CD's sometimes, the Case Logic will not at all. Its probably because the Fellowes gets moved around a lot more.
Do not buy one of those cheapo cases from "Uncle Chan's Bargain Basement" or something. They will destroy the discs in almost all cases. They usually do not use friendly materials, and do not really test the design. Case Logic has always done well for me.
NEVER store a cd case on top of a stereo system, computer monitor, refrigerator, etc. Keep it away from heat sources. Avoid leaving them in the car too. Thats almost an impossible task in itself, so all of my "Car CD's" I consider disposable.