I had an awesome session yesterday on a 6m Wave in cold frontal Scottish winds averaging mid 30's with gusts to the mid 40's. The 6m Wave was just very easy to use without actually being a dull kite - it was predictable and solid with good feedback and you can fling it round the window with pinpoint precision.
If you have ridden the 9m Wave you might feel it a bit lacking; however with the 9m being such a standout kite you need to forget it and take the 6m on it's own merits and it is a cracking high wind kite. With it's speed, precision and forward turning you can really give it some beans in crazy winds to get some huge jumps and the landings are not as frenetic as on a C kite (I ride Razors usually) where you can redirect or really whip it through a fast downloop for silky landings.
The Wave series has been the only kite to make me think about giving up a C as they really are a little bit special