AS30 is goose feathers while AS3 is duck, never used the duck feather yonex but i heard they're pretty good.
AS 30 is for professional players' training. AS 03 is made out of duck feasters. Flight pattern is good but the durability is not very good. The price difference is almost double. What do you expect?
thx man, that makes it very clear. tried AS30 this morning, it is good but as you said, it is double price of AS03, can afford to play with it all the time. by the way, heard aeroplane EG1130(black) is very good, going to try it this sunday.