My 4 y/o likes it.  We got it for Christmas and it was initally lost in the crowd, but the first time he busted out his other knight paraphernalia, he forgot he had a new helmet.  He ran back to grab it and the excited cackles were awesome.  He never puts the visor down, but it stays up and doesn't fall down.  He's averaged sized.  It is a little shallow, so he has to hold it on his head when he runs, which he's totally not supposed to do in the house anyway.  Overall, happy with the purchase.