I find them to be an absolute curse when the video maker has a large enough impact/over all audience. NA was going ballistic over it a couple years back and off and on ever since. Someone actually went as far as correlating the videos on Cinemassacre by Mike Mattei with the horrid uptick in the price of games both on the NES and SNES. Shortly after those suckers went live back then the prices on things like Hagane, Run Saber, and various others rocketed up just after the fact. Various other polluters like Game Chasers have done the same, but also magnified the problem horribly so in their local areas and are well known among collectors as a curse to any store they've hit in the Texas/Arkansas areas they roll to. People learn they have stuff and for low prices after the video and find where it is, the store catches on shortly after and all the prices escalate a lot and the stock/variety drops because their regulars and informed types stop buying and turning stuff in because they get screwed on both ends (trade and pricing.)