I've had some delivered today and they are wonderful. The last two tops I made had lightweight fabric and while I could manage to get double fabric to work on the coverstitching, the minute it went onto a single fabric, tunnelling. So I've thrown the towel in altogether and I'm not even going to bother trying on any kind of fabric. They are Klasse that I got from Jaycotts, more expensive than some I have seen, and they sort of have bends on the handles, which makes them so much easier to use.
Absolutely flipping perfect