I've found Catalysts to be a really fun kite for riding strapless surfboards. They have a light, direct feel and turn fast with smooth power. They allow your board to follow the water without that feeling of being lifted yet provide enough pull to accelerate you around long fast sections.
I've got a 6m, 8m and 10m and riding a new 5'8" Wam, I tend to use them in about 25,20,15knts respectively. In WA I use each size equally throughout the summer. I've enjoyed my 10m in gusty 12-14knts and had it kitelooping in over 25knts. I've also been impressed with the performance of the 6m in just over 20knts (I'm about 70kgs).
I think the REO is going to set a new standard for dedicated wave kites. I had a chance to ride some of the earlier protos and they were very impressive. They had a really smooth, direct, responsive feel and loads of depower. They drifted down the line making the fastest of sections and provided a smooth, consistent pull through turns. Apparently everyone who tries the latest protos wants to own them

If most of your riding is in gusty onshore conditions, with the occasional freestyle session, i think the Catalysts would be an excellent option.
Hope this helps
Nath
Disclaimer: Team Rider for Ozone and AKS