I've read some complaints about the color turning yellow in some MC speedies. Has there been other problems with the MC speedies? Does it stand the test of time or does it end up looking old and saggy? Who owns a MC speedy, and who can tell me how their bag has been? Are you guys overall satisfied with the bag? Also, is it really going to ruin the bag if I leave it in the car during hot days, like in the summer? Thanks for your help guys!