Rob,
I think a lot of collectors cross buy so to speak and, don't think there are many really who buy just one companies work There will be some but, on the whole how many collectors on here could say, I have nothing but this manufacturer. There is so much to choose from and its nice to vary things.
I thought the whole point of these sites et al was to discuss products and included in that would be constructive critique of the available works. I go on different manufacturers and do that but, I buy from a range of makers from Matt to glossy but, I don't think its wrong per se to say that a set may not be up to expectations or that you do not like it as long as you can support the argument and stance you have taken.
Ridiculing or, antagonizing collectors of one maker is something that I would have thought the moderators could stop quite quickly though, I am not telling people how to run the site.
There is some who enjoy winding up others and every site will have some who value this over proper debate.
Mitch