The only real negative I've heard about the Wii2HDMI dongles is that some people have reported that it's caused their A/V port to go out after awhile because the adapter requires a little bit more power through that port than normal Composite/Component cables require. I have no idea how you tell which ones are good as opposed to which ones are bad, it's all coming out of China after all, and the risk is pretty low considering if the Wii breaks, a replacement is what, $40 or so?

So, I'd say get it if you want the convenience of using HDMI. From everyone's description, it's still not going to be as good as using a WIi U, but that's cost prohibitive, and this isn't!