I have been offered a PhD at a TOP institution. The problem is, it is in rather an applied field. I am also waiting upon an offer from ANU (Australian National University) in a fundamental topic. Both are world recognised universities, though the former is of the top few. My worry is that I will be pigeon-holed after my PhD and be very restricted in what I can do after. My question is: how much does our PhD tie you down to the project you study, and are Australian universities well regarded to the extent that do their graduates get positions in world-leading institutions, such as those in the US and Europe?