Through experience and many damages, I have come to conclusion that seam rippers are possessed! I have been sewing since the age of 8 which means 54 years and I have had many mishaps. Seam rippers are like automobiles... a necessary evil! I am now retired from corporate America and now have a very fun sewing and alterations business in my home. I use seam rippers every day and HAVE TO BE CAREFUL. Yes they dull very quickly when you are ripping out blue jean hems. The biggest mistake is pushing too hard because the thread will eventually let go and if you aren't ready to handle the force you are putting on the ripper, you will have a very expensive glider ride right through your fabric. I keep dozens of rippers at a time because they dull. My suggestion to you is to go to Wawak online. It is a catalog for sewers. I buy the little blue seam rippers for pennies on the dollar and I do believe more mishaps occur with dull ones because you are putting too much pressure on them. The savings on thread and needles etc in this catalog is HUGE. They will also send you a catalog and you can call the 800 number and talk to their very friendly staff and place an order. I never buy my thread or needles,etc from a fabric store anymore. I have saved huge amounts of money by ordering.Not sure if you are a seamstress as well but they sell invisible zippers for 59 cents each, blue jean zippers are just as cheap. Good luck with the "evil ripper". Marty Byrnes Mesa, AZ