I have been overpowered on 20M kites (20-30 mph), and overpowered on 9M kites (40-50 mph). Neither is fun. Around here we call that survival kiting. Sure it is doable, but high risk. I am thankful that manufacturers are making small kites (some manufacturers smallest was 9M in 2004). The cool thing about small kites is they start in the low 20s. These days, I have more fun with a 5M in 40-50 mph winds, than a 9M. A couple of our recent bad accidents would have been minimized if the out of town riders would have rigged a kite smaller than their 9M. And when the winds are stronger, and my 5M starts feeling like too much kite, I will drop to a smaller size. I've witnessed a 5M waroo unintentionally looping in strong winds, when after a crash, the rider's hook fell onto one bar winder.
Just remember things happen faster in strong winds, respect the wind's power, and know your limits. If you don't feel comfortable looping the kite, rig smaller, or throw in the towel. I have no shame not pumping up on days I failed to bring a small enough kite.