Got um in early '08 and WOW just WOW. I would highly recommend them. I do use the thumb shifter its a great design for me.
Well I guess you love em or hate em. I'm not a big fan of em, but I guess its preference. First off, I don't like rapid rise derailluers. Since the spring is most relaxed in the easy gear, the second the cables get fowled out, it hard to shift to an easier gear. I'd much rather be able to shift to an easier gear rather than a hard gear. Also, I find when your on the brakes, it's extremely hard if not impossible to downshift. And lastly, it might have changed on 08 dual control, but on the earlier setups the left shifter was such a hard throw that we had to switch out the shifters for several women because the simply couldn't shift the left side with their small hands.
These are just things I noticed and my opinion only. Ya won't find them on any of my bikes.