One piece 海賊王

How many of the One piece 海賊王, I do not know how to choose it, I feel that if I like it, I will certainly buy type, but if my children didn’t love, then I will want to change a, then he will be very happy, but I don’t want to think, because it is no necessary, One piece 海賊王 there are many different styles, I still want to do the comparison can, I think I and my family together, I said I give my children bought One piece 海賊王, if they love what you say your child is not possible, but I don’t know what to say.