My aunt (graphic designer/art director) said that whatever my first job is I should be prepared to stay there for at least two years and that if it was a company I wasn’t willing on working with for that long I might want to look elsewhere.

I think the most important thing is finding a company you’re comfortable with, both on a personal and professional level. If you are leaving for greener pastures I think it would be best to make sure that not only is the pay better, but you like the kind of work you’d be doing better and that the studio ecosystem is more to your liking.

In short: Only change jobs if the new job will make you happier. Besides, if there is something about your current job that does make you unhappy, you can always try talking to your boss. If you have a good job they’ll listen to you. If they won’t even listen then you know to leave.