I love my Bucks (110's &112's), but I can't adjust the pivot, there's issues with some: off center grinds, slight blade play over time, one had a strange clicking in the handle which I returned, another developing a weird roll or chip in the blade (I think it's from touching the inside when closing), and even over sharpening from the factory taking years off of the life of the blade. I still love the knives though. Check the Buck section to see how many boxes collectors go through at Cabelas to get that "perfect" Alaskan Guide 110.
I only have a few Spyderco knives but they are all over $100. One had a slightly uneven grind, and another had a thumb hole which would wear apart my winter under gloves before I sanded it.
Of the 3 Esse Rat folders I had, one had defects on the blade under the washers which caused gritty opening. I've also had issues with some LM blades, but don't carry my Vics enough to notice any flaws.
My one CS knife had an off center grind and an oversized pin in the handle I had to grind down so the handle scales sat flat on the back spacer.
I have around 15 BM knives and only sent one back for repair. Another I sent in because I messed up the blade. Their CS was awesome. A couple have grinds that are about 1/2 mm off, but nothing a good sharpening didn't cure. Personally, factoring the added expense of labor for the more intricate inner workings of the Axis lock, an American factory, excellent CS, and upgraded options both in gold class and dealer exclusives, I don't believe they are overpriced or falling behind in design. If anything, I think they are lacking non-Axis lock manual offerings, but that is also one of their claim-to-fames.
Nowadays I always place in the comments to knife dealers to check for blade centering and lock up before shipping any brand out. I also like to take my knives apart and thoroughly clean and oil them when I first get them (didn't Spyderco use red loctite on their screws until recently?). Maybe I just need to collect more of the other brands to get a better sampling, but at this time, I don't see quality control lacking in comparison to competitors... at least in my experience.