I've sent two knives back to Spyderco- not for warranty, but for wear issues. They have been outstanding in their customer service in my experience.
I sent a very early Delica with a stainless steel handle to them because the clip had lost some screws. They replaced the clip and also the blade (which had been chipped at work, my fault). Later I sent a 1st gen Native that I had bought at Walmart for another clip related problem and I think they replaced the blade on that one also. I think the turn around was 2-3 weeks. They really took care of me and I've bought many Spydercos since.
Serrated Manbug. Recent acquisition based on posts different thread (NPE) this forum. Lot of knife in a very small package.
Anyone seeing finish issues with Seki City knives? I was handling @Flamingo's new Waved Delica today. And for the most part it was precisely what I expect from Spyderco, except the finish inside the Spydiehole. It was rough, there are visible tool marks inside of the hole, and a noticeable edge/burr all the way around the hole. The edge caught my attention when thumbing it open, it was almost, but not quite sharp enough to slice my thumb. Looking closely then, I saw the tool marks. I ended up breaking the edge down with a fine stone and running a buffer and some polishing compound inside the hole. That made the tool marks visible but not feelable, the edge is present but softer. You would probably have to more aggressively go after it to get it really clean, since it's a hardened blade.
I have not previously encountered a Japanese or USA made Spyderco with that lack of detail in finishing. The tool marks really caught me by surprise.
I guess, I expect that kind of finish on a $30-60 Chinesium knife, even a Spyderco. But the Seki City knives have always been a step up from those in my experience much closer to USA made stuff (and sometimes superior to USA made knives). In particular because a Waved Delica is basically a $100 knife, I find it a bit off putting overall.
I can’t say that it was unfinished as you describe, but my recently purchased Stretch (a Seki City knife) had the sharpest corners on the Spyderhole I have ever experienced. I broke them with some 400 grit emery cloth, much as you did, but have not yet tried to go after it with some polishing compound.
When I looked on one of the Spyderco forums that Sal Glesser started and moderates, I noticed questions about why the holes aren’t chamfered and finished like they used to be, and Sal actually answered himself and said that if they are chamfered and polished, they get away from some people (thumbs slip off/out of the hole) and there have been injuries as a result, so they have been leaving them sharper. No burr, but square and sharp.
Made sense, but I feel like it has gone too far the other way now.