My son, 10, has asked for a Water Worm ( http://www.waterworms.com) for his birthday after seeing their commercials. They look pretty fun, but I’m wondering how durable they are. He of course would like the large 6 lb. size, but I don’t notice them being demoed much in the commercials and pics, so I’m also wondering how unwieldy it would be for a 10 year old. I can’t find any mention/review of them on Amazon/Toys R Us site, so I’m looking for anyone with firsthand experience. Thanks!