Yes, it can be extremely good fun! Of course it’s also a lot of hard work, but most of that work is enjoyable. I love the fact that I spend a lot of time DOING things, rather than sitting at a desk working on a computer.
Science, like any other job, is as enjoyable as you make it. If you get to you know your colleagues and get on with them, and get pleasure from your job, then it is very enjoyable.
Add to this that being a scientist means you are working towards expanding human knowledge – you are rewriting the textbooks and pushing the boundaries of understanding and, potentially, improving the world beyond recognition. AND you are working in a challenging, important and interesting field, which makes you proud to tell people that “I am a scientist”… Well, what else could you want from a job?
It is a lot of fun, because you always feel that you are discovering or understanding things that people didn’t know before. At the same time, one of the first (and hardest) thing that you have to learn as a scientist is to accept failure, because experiments often don’t work and don’t give you the result that you wanted. Those moments are not fun, but if you are able to see a failure just as a new challenge, then I think you can be a great scientist and enjoy it a lot!