Even with the 220 i'd say it needs 'bullying' around the sky, it has no momentum (normal for big really light models-especially with the ship anchor amount of drag this one has :-) ) It's about right, I spotted for Steve on his first flight yesterday and talked about getting on the power early, its fine like that and did nice large loops.
I don't think he has one way valves, would need to check, I had little to do on the build other that supply some of the equipment
Dave