FishAndChronic:
In all honesty, they're pretty ****** bottles. You'd be better buying a real bottle of Lucozade and refilling that. Far cheaper.
they are much thicker and more durable plastic, ideal for sports where they shall be chucked around and thrown in kit bags. so no, it is not more suitable to buy a normal bottle and refil it. this will go out of shape and is not designed to be refilled time and time again