I know a lot of kids who still use sippy cups - there are plenty in cool colors and designs if you want something less baby-ish, but he's not even 3 yet. It's going to be a few years before he's careful about spilling. There are also bottles with built-in straws - get one that is leak-proof. As he gets older, you can get the kind that I have that I take in the car and to the gym. You can get them at sporting goods places like Dick's, and they have a folding mouthpiece/straw - however, you have to kind of bite down on the "straw" to get the liquid to come through, so that might be hard at this age if he has to squeeze the straw with his teeth and also suck at the same time.
When you buy any bottles or cups, be sure they are made without the BPA plastic that is so harmful. All the advice now is telling us not to use water bottles from the water companies - they have harmful plastic, they are subjected to high heat when they are transported from plant to supermarket, and the water isn't regulated at all (or even filtered half the time). So those bottles should not be purchased or re-used.
I think it's important that kids stay hydrated, and that's why all the cars and strollers (and even the grocery carriages) are made with cup holders! Definitely take water if you don't want him to have too much juice, but take something. A lot of times kids (and adults) want to eat when really they are just thirsty - so having access to liquids can help long term in preventing over-eating and even obesity.
All the kids in my family used some form of sippy cup past 3, and my granddaughter is almost 5 and still using one.