I've had this machine for almost five years and no big problems. I've used all kinds of thread. I've noticed that when a dealer says you have to use only a certain brand that's the brand they sell. I don't think that's a coincidence. You do have to be careful about the thread coming out of the take up lever and I also use a sew-on/sew-off square when I'm piecing. Hope your dealer can help you. If you can get the problem solved, I think your wife will love the machine.