Personally, if I'm using a Cherry MX based board, I vastly prefer the PCB mounted switches to the plate mounted. I still don't like them that much, but I don't hate them as I do the plate mounted versions.
To answer the original question, no, inexpensive mechanical keyboards are not bad at all, but may not be what people exactly want, if that makes sense. Personally, I would go with an inexpensive old Model M that I refurbish over a new (almost) anything. But that's because I genuinely enjoy typing on them. Try your G80. You may really like it. Price isn't always indicative of quality, after all.