I have a Tin Lizzie 18LS and was also recommended to use King Tut in the top and So Fine in the bobbin. I have only had my set up for about 6 months, and have done 6 or 7 quilts on it. On all but the last quilt I used the King Tut/So Fine combination and had very, very good luck. Worked very well. You get a lot of lint in the bobbin case with King Tut, but I just cleaned the lint out of the bobbin area every bobbin change and had no problem. It cleans out easily. The last quilt I did required deep purple thread (it was a Washington Huskies quilt for my grandson). King Tut didn't have a thread that was the right color. While at a quilt show I found Omni thread (also a Superior Threads product), and they had the perfect color. I bought a cone (much less expensive than King Tut) and used it in the top and bobbin both, and had no problems. I still love King Tut and will continue to use it, but I'm happy that I have found another thread Lizzie likes. Omni doesn't give off the lint King Tut does also.

I just checked the Joanns site, and if you search Superior Thread, you will find they have a small selection of King Tut.