Honestly, I think if I'm going to keep reading this series, I ought to stick to the Cordelia books. I have nothing against Miles, but the way he's written is a little insufferable. While Cordelia is also ultimately always right about everything, it's somewhat more refreshing to see that in a female character. Reverse sexism strikes again, I guess.
I also just prefer the culture clash and political backdrop of these novels to The Adventures Of Sexist Baby Genuis With A Chip On His Shoulder. Cordelia is, I think, supposed to be an unreliable and biased narrator at times. Maybe that's something Bujold is trying with Miles, but I've never gotten that sense personally. With Cordelia, her super-liberalism is supposed to be lampooned as it contrasts with the super-conservatism of Barrayar, or the central conceit of the book wouldn't work. I personally find that much more engaging to read.