I think the expectation of the Generation NEX being the end-all be-all of NES clones to be a bit harsh, Jagasian. The console is no doubt flawed: obviously, Castlevania 3 and a small clump of other games refuse to work, and some other games are marred with bugs. Aside from Castlevania, the only other thing I've noticed were some minor color changes; quite noticeable but nothing that affected gameplay at all.
The fact that Messiah "lies" in their FAQ is something to be concerned about, I suppose, and that this is a 10 year old chip and not a custom made one kind of stinks - but the entire console is a CHEAP sixty dollars. So it's not 100% compatible: big deal. My old NES is barely functional if I'm lucky. The fact that I can pop in all of my old games and have them work damn near flawlessly is reason enough to love the thing. I don't know anyone, in fact, that has an NES that runs nearly as well in this day and age. Perhaps the top-loading ones are still in fine form, but good luck getting one cheap on ebay or anywhere.
Someone said there was a difference between advertising full emulation and backwards compatibility (in addition to the primary product). True, this is an emulation machine that is expected to run all games. But is anyone honestly replacing their NES with this? Anyone who's even interested in one, I'd wager, quite probably still has their original NES or has acquired another by now. This is merely a complimentary system in my eyes - one that tries to rekindle the spirit of the NES as faithfully as possible with an extremely reasonable price point.
The fact that my family, who hasn't touched a video game not called Solitaire since the NES actually sat down in the living room and played with me speaks levels about how successful the product is. It isn't perfect, but it is well worth the asking price, and then some.