I'm sure others will chime in, but my two cents worth is the full vent. I'm relatively new and learning but contend more with light wind. I flew a mid vent in 10-12 and loved it. Last weekend I was out in 42 deg F with 15-16 mph winds steady. The full vent was perfect in that wind. Controllable, smooth a real pleasure to fly. I spent over two hours flying the same kite. It was great. My first kite was the full sail and when I had it up in strong winds it was over powered and hard to control. The full vent will be hard to keep up when the wind drops below about 12 mph, but if you get steady wind around 15 mph I would get the full vent.
I also recommend finding some fellow rev fliers to hang out with early on. I struggled until I went to the Carolina Kite Festival where I met several great people who seemed to fight over the chance to help me out. I finally "got" it and have been on a tear ever since. Also watch the JB videos on all the basics. Set up, lines, basic flying. They really help. I'll add one tip of my own. When you are done, make sure your lines are straight before disconnecting the kite. Even if you have to rotate it by hand to undo the twists, do it with the kite connected and some tension on the lines. My first flight was on 100' lines and simple things like snags, etc got me twirled many times. I thought I will untangle them at home and disconnected the lines. I'll never do that again. It took my son, his GF and I over 3 hours to untangle that mess.
This forum has many flyers from the UK. Meet up. If you have 15+ mph they will probably seek up out.
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