i have to repeat my cautions:
1 - expensive does not guarantee quality.
2 - "egyptian" in the name or description does not guarantee quality.
3 - threads that work well for some people on some machines may not give the same results to somebody else on a different machine. you may even find differences between machine models from the same manufacturers.
4 - buy only one or two of each new brand you try, and then write down the results. that way, you'll learn which to buy in future and which to avoid. experiment, starting with the less expensive brands, working your way up the price scale until you find one you and your machine like.