It won't be as good as the Nexus 4, that's for sure. The components will generally be lower quality, I wouldn't expect too much from the camera, and it will be manufactured in China with slim profit margins. I'm sure it will have some flaws, there is an issue with the GPS, apparently common to phones with Mediatek chips, but there is a workaround for it.
I'd be wary of companies offering it for as cheap as $140, you may not get good customer service in case of a problem with the phone, which is more likely for a cheap phone like this. I ordered mine through Dracotek on Amazon.co.uk (they do have their own website) and they at least have a good reputation for customer service.