Of Manhattan's books, I would say their Logical Reasoning book was the most helpful for me, and their forums are great to get explanations from the course instructors. Almost all the questions on the LSAT from ~1-78. have been solved on those forums, so it's a great resource--but access to their forums is free.

I was already good at LR, and get like questions 1-18 almost always all right. But around question 19-25/6, I would miss 2-3 questions for a lot of reasons--psychologically I was rushing because 1-18 took too much time, 19-25 are known to be on average much harder, etc. And, it seemed like under the timed conditions I couldn't choose between two answers for a 2-3 questions, and I would rush the rest.

I decided to relearn how to do LR questions via Manhattan, and really drilled the methods and got very good at not just identifying the right answer and prephrasing, but more importantly knowing why an answer was wrong and leaving contender answer choices. And, I would definitely say by slowing down on the understanding of the question and stimulus, the confidence and speed came over time.

Their RC book is also good--but RC is more dependent on you and their is no one-size-fits-all strategy for that. Their RC book helped me, but it's not for everyone.