I've finished a second reading of Master and Commander, and certainly will not want to wait till September to read Post Captain, but perhaps I can hold off on comments on that one till later, if I read it ahead of schedule.
One thingto note is that (from my creaky memory) Jack’s comments in the film about Nelson appear to lifted from the first book.
I had read it 27 years ago and liked it, but this time I liked it more. What marvelous storytelling! I admit I did keep thinking of the movie, which is probably my favorite new movie of the last 20 years. That probably did color my reading experience -- but what a book, even allowing for that.