Lots of great opinions on this topic. I had two thoughts.
First, why should homerecording give these companies a free voice? If they paid a fee to help the board, I don't think that would be unreasonable. They could say what they wanted about their gear--but we'd be able to ask the difficult questions and they could say something besides "You'll have to decide for yourself, otherwise I'll be accused of spamming."
My second thought was: Why don't these companies open their own forums on their web pages? The answer is obvious. It kills the mystique for any popular product. Some guy comes along and says he tested the Audio Buddy (or whatever) and the frequency response is better that their brand "X", and all hell breaks loose. You get a lot more mileage by not addressing any controversy than you do by inviting it.
The best endorsement is always by the user. I imagine this forum has helped to sell a TON of RNC compressors and the builder doesn't post here (as far as I know). SP has sold a ton of mics on user feedback too. Does Alan Hyatt's presence here add to those sales. Probably so, but he doesn't come in and say that I'll be disappointed in the V67 when I hear a C1. For that reason, I respect the guy.
Thats why I thought of the manufacturer's forum. I think it would be valuable enough to many of the members here to consider. But remember--it could be a double edged sword for the gear companies too. Instead of having the escape of saying "I can't really discuss this because it will be considered spam" they'd have to put their cards on the table. Sometimes they'd have to defend themselves against what someone considers the shortcomings of their products. If I were making a product, I'd have to be damn certain of it before I'd go posting about it in some forum.
I don't know that a manufacturers forum is the answer, either. It seemed like a way to resolve a big conflict here, but it might be doomed to failure from the get go.
I'll tell you the aspect of Alan Hyatt's presence here that I like. When SP is coming out with new stuff, I get to hear about it. I have an interest in his preamp and in the TB1, so its great to get that info here. Also, things like the reintroduction of the Meek preamp that was discontinued. If he doesn't post, we don't hear about this stuff. For me, and many others, thats valuable to know.
Well, those are my current thoughts. No final answer, but a bit more to consider.