Loved Pandora's Star. Then read the sequel. Pandora's Star was actually the second book in the series, but put off reading that one and started the 4th book in the series which takes place a couple of thousand years after the third. Not liking it as much as the other 2, but giving it a chance.
Finsished the 4th and 5th book in the series and half way through the 6th. Books 2 & 3 were sci-fi (again, I skipped book 1) where as books 4, 5, and 6 kind of tell 2 different stories- 1 story line is sci-fi while the other storyline is more fantasy. Generally don't enjoy fantasy, but have liked both storylines enough to continue reading despite not liking 4, 5, and 6 as much as I liked books 2 & 3.
Despite being somewhat frustrated with Peter Hamilton's plot development (he brings up a lot of interesting ideas that go in directions that are unexpected but I don't necessarily like), I've continued reading his work.
After finishing his Commonwealth books and skipping the first, I went back and read the first book. It was indeed skippable as it didn't add anything to the series that followed.
Then read "Fallen Dragon" which I enjoyed.
Now reading his "Night's Dawn" trilogy. Liking/hating it just as much as the Commonwealth books (well written, but takes some unexpected turns and some of the turns are kind of dumb).