I have had one for a couple years and it is great for the tasks of an every day knife such as; cleaning fingernails, scraping gunk off things, opening letters and boxes, etc. It is convenient and it becomes an unconscious action to access it. I was checking into a hotel while on a cycle trip when a woman behind me offered me a coupon for the hotel. The coupon was in a magazine so, without thinking, I took the knife out, cut out the coupon, and stowed it. When I turned to give the magazine back to her, she had backed away from me. It was such an automatic action that it was over before I even thought that it may make someone uncomfortable. I live in a small town in northern Minnesota and most of the males carry a pocket knife. The last use of such would be as a weapon. A knife fighting instructor once said, "If you get in a knife fight you want it to be in an emergency room".
My only problem with it was at the Saloon No. 10 in Deadwood, SD. My buckle caught on a the back of a chair, I heard a thud, and the knife was laying on the floor in the sawdust. I quickly retrieved it and apparently no one noticed; however, it gave me a quick shot of adrenaline.