Agreed, the Song of Albion series is a great one, I'd certainly recommend it to fantasy fans.
I read The Way of Kings and thought overall it was very good. I wasn't too keen on some of his magic system in the book, but I'll definitely continue on with the second one, Words of Radiance, which is due out in November. You're right, though, by the time the last book comes out, you'll probably have to reread the whole series to really be on top of things.
I'm currently reading Daniel Abraham's Dagger and Coin series and recommend it too. Some of the protagonists are definitely anti-heroes, you kind of like them one minute, then hate them the next, then kind of like them again - it 's never for sure how the author wants you to feel about them. Characterization is very strong and the books are well-plotted, overall very well written. And definitely for adults, which can be a nice change, with so much fantasy these days skirting the YA line.