I have a pair of RS30s.
I have only ridden them a handful of times though, so not in the best position to give an indepth review. They seem pretty nice wheels, not particularly light, but climb as well as my handbuilts (I live in a very hilly area).
When up to speed the rim and bladed spoke aerodynamics (and possibly rim weight) mean that they seem to hold their speed really well.
I have read about RS20 spoke breakages but the RS30 uses the same spokes as the RS80 and the rim is pretty deep and very stiff, so hopefully should be be robust.
I have also heard about Aksium spoke breakages, esp on the more recent models.
A bit waffly I am afraid, but basically I like my RS30s.