I definitely have my preferences on makers/brands that I trust will be stellar out of the box (note, not necessarily sharp, but well made with no 'problems'), but I wonder how much of that is really a reflection of the actual maker/sharpener, and how much is a reflection on the vendor who inspects and actually then sells the knife?
no doubt it's a combination of both
I'm absolutely convinced that folks like Jon and Maksim are personally inspecting every blade as a last-step quality measure, and they catch the occasional overgrind or warpage/mismounted handle so they don't actually reach us as the consumer - I trust them fully, and I've not had a problem from either of those vendors - but I have seen real overgrinds and mis-mounted handles from other vendors, so would actually prefer to purchase knives from them in person where I can select my own. A quick trip to the shops in Japan will show that these problems are fairly common (although the stores in Japan that I've purchased from are very accommodating and will fix/exchange/select the best, etc, IME)
I suppose it still doesn't answer the question of who the top makers/smiths are... my votes go to Hideyaki Yamamoto, Tokifusa Iizuka, Kenichi Shiraki, and Kiyoshi Kato - folks already mentioned here. But to be honest, while these are among the most outstanding knives I own my opinion of them is formed by only a few examples of their work (in some cases just one!) and they're the ones most readily available in a fairly narrow price category. I'd love to hear a short list of the best smiths from a sharpener/polisher (and a short list of sharpeners from a smith...)
realistically, the best makers IMHO are the ones whose knives you're reaching for most often