I have some aurifil thread and some other brands too. I do have to say of those that I use, aurifil is by far the better thread of choice. It doesn't build up much lint and it doesn't take up any space in the seam allowance like some other threads even tho they are 50# threads can make the quarter inch seam more bulky? I don't know how else to describe it. It is very pricey but worth not having to clean the bobbin area very often. The other one I like is mettlers silk finish works somewhat like aurifil but doesn't seam to get the mileage you get with aurifil. Just my personnel opinion.
Suzy