I've never heard anything bad about blems from anyone, and most of the time people receive blems which they say they cannot find the cosmetic issue on them. With that being said, I just received a 1670CF154 blem last week but had to exchange it for a new In box. The knife functioned perfectly but this particular blem was very noticeable. Out of its bag, the edges where the CFinlays sits had what seemed like excess glue on it ( alot and very noticeable, some on the spine also). I thought, oh that is the blem no worries a little bit of effort and I can get it all off which I was able to get most off in one try. But then I compared it to my other one which was not a blem and noticed that the inlays on the blem protruded out more than the nib, I was like "no prob"...until I tried to place the clip tip up and learned that the protruding inlay wont allow me to properly fit the clip because it got in the way which was the deal breaker for me (modding or flexing the clip just to fit it is too much effort to save $20 on a blem and is slightly beyond cosmetic in my judgement)I fondled it some more along with the nib one and realized that one inlay on the design side and the entire inlay on the clip side was not securely fit compared to the nib, tapping it with my fingernail you can tell that it is hollow compared to the other which is solid. Would have been happy with a blem as a user, but in this case, I felt that $20 more and I get a new one with warranty. Dave took care of me no questions asked, he effin rocks and look forward to dealing with him in the future. With that being said, blems are good to go and I'd still get one in the future for either a user or if that is all thats available. You must take some risk in getting a warranty voided product, and my experience is practically the only I guess you can call negative (if even that) one on a blem.
I now have three non blems of this knife... I got another on the way. I dont own any knives with the exact config in triplicate which says alot about the knife.