I muddled my way through the first book, but the second one completely lost me. I think that Gabaldon's details, while incredible, end up losing the story after a certain point. Too many time-skips and back and forth. I couldn't pick up the book and immediately follow it. I found Claire had lost a bit of her spark in the future, and her daughter was a vile creature. It frustrated me to have the story jump back and forth between the current future and the past. I was also disappointed that the story skips ahead 20 years into their lives. Why? Did nothing good happen for 20 years?
At any rate, I wasn't impressed. But again, I am a harsh critic of sequels. If you would like to continue in the series just because it's another book by the author dealing with the same characters, you'll probably like this.
If you want an independent, engaging story you can immediately sink into without having to re-read the first, I suggest you look elsewhere.