I am a member of his Forum, but don't participate because RC is excellent and there's not enough time in the day for RC and research as it is.
I think Igor you have hit the nail on the head so to speak regarding the lack of success of the Lost Cousins Forum. Rootschat being an established forum with a large membership has meant that the LC Forum needed to play catch up from the start. Unfortunately, in restricting the ability of people to join the forum, something that still continues, it was always going to struggle to compete and, as both I and others have said, the apparently cliqueyness (don't think that's the correct spelling

) of the forum adds to its problems.
As to experience of communication with Peter, well I've experienced both sides of his character. I have emailed him in relation to help clarify a couple of things he mentioned in his newsletter and received a polite response, one of which he was grateful about because he wasn't aware of the change of terms in relation to usage of the particular service and updated the newsletter accordingly. However, I have also had a somewhat heated discussion with him when he insisted that ancestry had been hacked the other year when it suffered a DDoA attack because for me the use of the term hacking was somewhat inaccurate and could lead to anxiety amongst those who weren't entirely familiar with what had happened to the site (it wasn't hacked, just taken offline by too much internet traffic).
Whether a minority or not, people's views of Peter will be coloured by their experiences of communication with him and, to be frank, some do appear to be somewhat rude. That obviously applies to many situations and is not just restricted to LC, but for someone who is running a business (namely the LC site) a little more diplomacy when replying even if he is very frustrated with people wouldn't do any harm to limit negative feedback as has been seen on this thread.
As for the LC Newsletter, in the past I've always thought it was very informative and useful, however over the last 18 months I personally think it has become rather limited in what has been included and I've found out far more from other sources, much of which he hasn't included when his next letter was released. I suppose some of this may be down to him concentrating perhaps more on his forum and less on the newsletter. But again that is just my personal opinion.