This is the first time I worked with "Spaghetti" threads from Wonderfil. They are #12, which means they are very thick BUT I didn't have any trouble to sewing with them. I used number 100/16 size needles and went a little bit slower with a regular home sewing machine.
I used to work with double #40 threads in the same needle but the end result is not as beautiful as this thread. I will continue experimenting with it especially with my mixed media quilts which are made from paper and fabric.
I'm just a happy customer :)