ever since starting to use clips i rarely use pins, i find they’re less of a safety hazard as i work on carpet and they’re less fiddly to take out when sewing. i usually work with thick woven fabrics or quilting cotton and find them very good for both. ive bought these from amazon twice and both times i have found that how easy they are to open depends on the colour, but they’re all fairly easy to open. i really prefer them to pins.