If you want a designer water bottle for travel, make sure you get one that is going to be worth the price. There are some bottles that look very fancy, but are actually quite slippery to hold and aren't particularly convenient to fill either.
Then you have the ones that leak chemicals into the water if they are exposed to sunshine, and the ones that encourage bacteria to breed around the rim.
If you are going to be drinking questionable water, you might want to look at bottles that have UV sterilization incorporated into their design, or at least making sure that you've got more than one bottle so that one can be left with water to be cleaned with iodine while you drink from the other.
A water bottle can be a valuable travel accessory or it can be a hindrance. For something so important you really want to make sure you get the right kind.