I've heard great things about "Once a Grand Duke" but mixed reviews of "Always a Grand Duke". Maria Pavlovna the younger's memoirs seem to get positive reactions as well. Felix Yusupov's seem to be well regarded as well although I've heard that many details are exaggerated. What about the memoirs of Pierre Gilliard, Lili Dehn, Anna V. and Sophie B?
What are the most recommended, less well known, not so good, or in your personal opinion underrated memoirs?