Definitely worth the money. I study in the US, and go back home to France for the summer, and I got a kindle for that exact same reason. It's great I can have/order books at the drop of a hat and I don't have to lug 20 books in my suitcase each time. I've also never had a problem with it.
But i will say this, even though i love my kindle and think it's the best, I also got it 4 years ago, when all that was available in France in dowloadable books was the kindle.
Consider your options with the Nook, Ipad... that are out now, and see what is the best for you. I would still prefer the kindle to anything else because I know a lot of people that switched from kindle to another.