I use coats & clarks egyptian cotton...I don't like the thickness of the Gutterman thread it seems very stiff to me...I am going to try the Aurifil...I really haven't had any problems with the coats & clark like so many others have mentioned...My machines don't have a problem with the C&C either....I have the Diamond, the DSE, The Sapphire & a Pfaff 4.0....I like a nice flat seam and pressing does that for me...BUT...if there's something better I don't mind trying it.... Thanks for the info....