I purchased an endura 4 from knifecenter about 3 weeks ago and have kept it in my pocket for that time. It has mainly been used on food prep, cutting string and opening letters and I used it a couple of times to strip the protective coating off of electrical wires. Note to self: buy a set of Kleins. This is scary sharp and a slip almost left people calling me nubby. Let me start by saying that my only other spyderco is an atlantic salt and I do love it. That is what made me want the endura 4. It is light weight, cuts food like a chef knife no problems on utility just on the recess where it locks up at is so prone to dust collection I often times had to blow it out before using because I never heard the click and it did not lock due to pocket lint. Like I said the knife has performed solidly I just question it as an EDC now because if I were to have to use it in a SD situation I am afraid that will be the time that dust will be there and it won't lock and now the perp won't have to hurt me I would have already cut my own fingers off for him. Anybody else experience this problem with the Endura 4 or is it I just need more money in my pocket and less lint.