to buy thread is by the cone. I have almost used up all my spools of thread that I have purchased over the years and I'm not going back to them.
As you know my preference for thread is Superior. I use So Fine in my sewing machine, King Tut and OMNI in my long arm.
The only thing I have/had problems with was storing the bobbin and the cones. Not it is solved!
I went to Canadian Tire and bought
Best tip I ever found!
and yes, I bought the long tees. They come in two sizes so I got the 3 1/4".