There are so many good threads available now to choose from. Needle size is important so read the education articles on Superior website. It will give you all the info you need to know what thread goes with what needle. I am somewhat of a thread snob but it's mostly from knowing the quality of the brands. Egyptian long staple cotton is the best no matter what brand. Then the quality goes down in steps from that. Find several brands of the quality you prefer and then buy those brands when you find a sale. I stick with Aurifil or Superior Masterpiece for sewing quilt blocks. Omni or Glide for machine quilting. I use Sew Fine or Bottom Line for winding bobbins or Aurifil 60 wt for bobbins when I want cotton. I was given a sample pack of Quilter's Select thread and some Sew Perfect thread. I like them too. If you have access to a microscope, a child's will do, look at the thread through it. You can see some thread looks like barbed wire and will be like barb wire going through your machine.