Are these a good choice for the parks? do they stay cold for any amount of time? Also....can you mix a packet of drink mix into them or would it be filtered out as you drink?? If you use Disney ice, doesn't the water still taste bad?? If there's a better bottle than a Brita, please advise!! Thanks so much! I'll be pregnant for our July trip and am pretty concerned about staying hydrated! 



) when I'm drinking it to get a nice, big gulp. Haha!! I also agree that it doesn't keep cold long, but you can fill it up frequently, so I didn't think that was a big deal.