When I first converted, their website was instrumental in my learning about the errors of Vatican II and the New Mass and all of the other problems. So I owe them a great debt.
Same with me, their website was very helpful in my conversion to Traditional Catholicism - whether you agree with them or not, their materials exposing the heresies of Vatican II and Vatican II claimants to the Papacy are extremely helpful.
They also have great apologetic materials against Protestantism - their docuмentary on Mary's sinlesness and refutation of the Protestant doctrine of forensic justification, and shorter videos on Romans 8, Papacy in the Bible and Galatians 5:19-21 are terrific.
However, I disagree with them sometimes. For example I believe in BOD and BOB for those who believe in the mysteries of the Catholic faith. And I do not agree with their explanations of the Apocalypse and their belief that John Paul II was the Antichrist. I also think they condemn too many people and seem to think badly about people instead of giving them the benefit of doubt.
But I do not want to say they are wrong. Why? Because in these times with either no Pope or an antipope it is hard to say what is true and what is false. There are controversies and the Church is not currently able to resolve these controversies. Is the Novus Ordo Mass and the New rites of ordination and consecration invalid? I don't know, only the Church can decide. So before people condemn the Dimonds as heretics for not believing in BOD I ask you a question. What would you do if we had a true Pope who came and solved all the problems in the Church and condemned Vatican II and the Novus Ordo and brought the traditional Mass back, but he also condemned BOD and BOB. Would you humble yourselves and admit that you were mistaken or would you decide the Pope was wrong and seperate yourselves from him?
I agree with everything you said here. I think the reason why they are so hated is not only the BoD/BoB issue, but also the fact that they condemn as heretics anyone who disagrees with them over almost any issue. I can't think of a single Traditional Catholic priest or well-known laymen who would meet Dimonds' criteria of Catholic orthodoxy. They don't seem to take into account that we are living in times of great confusion, which they experienced themselves - at least Michael Dimond once condemned sedevacantism. And sometimes they have problems with making necessary theological distinctions.