Don't forget the Quilter's Dream products! While I will quilt a customer's quilt when they bring W&W or W&N, I prefer the QD products. I have had to learn to refuse the Mountain Mist products. They are inconsistent in thickness, which leads to inconsistent thread tension. I can't have a quilt leave the studio if people won't be happy, and I don't think they'll be happy with lots of thread pokies!!
I've also had some issues with W&W and W&N when using dark backs. Sometimes the batting pokes through with the needle. While they will eventually sluff off, it looks horrible when returning to the customer. As I understand it, this is not unusual with those products. I have never had that problem with Quilter's Dream.