King Tut is lovely thread but I have had problems with lint buildup with it. I still use it but I am prepared to check the tension more often. If doing E2E I check every row of quilting. If doing custom I will check half way between every advance. If you want to give your LA one more chance I would recommend Filtec Glide and try a jar of the magnaglide delights prewounds to go with. If you have a backlash check spring in your bobbin case you will have to remove it prior to using the magnaglides. Google them for pictures of what they look like.
Filtec (
www.bobbincentral.com) has gone wholesale only so to try it out you will have to find a retail outlet. Most likely you will have to order it on line.
Here are a few sources I just found by googling.
https://www.longarmquiltingsupplies....ilting-thread/
http://www.quiltscomplete.com/Depart...ead/Glide.aspx