Wow! I knew the kids enjoyed playing with my GX470, but I had no idea how uniting these things would be. I bought these for the 4 and 8-year-olds, but the 15-year-old came out of his cave and played with us, too. That was worth the price! The 4- and 15-year-olds get along well, but everyone fights with the 8-year-old. Seeing all three kids running the RC cars together made me a happy dad. Also,...