The solar ranking is based on a number of criteria including feedback from solar industry professionals and installers. This is an Australian based site and as such the majority of our feedback is from Australian installers based on the 2 million plus solar installations. From our hundreds of surveys we have compiled, Goodwe has had mixed feedback with some compaints from installers about difficulties claiming warranty and sub-standard service and support. However this has improved over the last year and the new models from Goodwe do look impressive. Time will tell.
As for Canadian Solar being number one? What is this based on, production volume, innovation, warranty, efficiency etc?
Canadian produce mid level lower cost panels using standard P-type silicon and have had several issues with micro-cracking and potential induced degratation over the last few years. While Canadian is still highly regarded they are not currently considered a module or cell manufacturing leader.
Hope this helps