for dd1 (almost 6), does anyone have the ones with pneumatic tyres like [[http://www.amazon.co.uk/Scooter-Small-Pneumatic-Drinks-Bottle/dp/B0002HZQ9G/ref=sr_1_1?ie=UTF8&s=kids&qid=1283965013&sr=1-1 this]] and are they worth the money?