Help! I need thread!

I've spent the last couple of weeks, and some time at Quilt Market, trying to decide which brand of thread to carry in the store. I have been a die-hard Star Cotton fan for over 7 years now, but it's just not cutting the cake any more! They've changed their weight and quality, and now it won't run through my Nolting without breaking constantly. Frustrating, to say the least. It also seems to leave a lot of lint during piecing and quilting. So...I am on the hunt for a new thread.
The problem is I have no idea which one to go with. My top picks so far are:

Signature, because it is less expensive but works well for quilting in the Nolting and for piecing. It's available in various sized spools, including giant cones. It costs about $4.95/500 yards.
Mettler, because it is superior quality and works great for quilting, although it doesn't come in larger cones for the Nolting. It's also $6.70/500 yards.
Aurifil, a brand recommended to me by a friend, but comes in 1400yard spools with seem more expensive (around $10) because you're buying more at once.

So, what to do???? Please leave me a comment with your favorite threads. Give me a reason why you think one is better than another, please! Would the price of the Aurifil scare you, or do you value the higher quantity and quality? Would you be more likely to spend less and go with Signature? Help me decide. I'm having one of those obsessive compulsive urges to buy a thread display for the shop!