I was offered a post doc position in a top level university about 2 months ago, which I have already accepted.
However, I was recently called for an interview in another equally prestigious university for another postdoc position which I applied to before getting the previous position offered.
The second position is, in my view, much better than the first one in many senses (I like the country more, a substantially higher salary, closer to my home town), however I am worried that if I decline the first offer (which I already accepted) now, the supervisor from the first university will get annoyed and that will carry repercussions in my future career and my image to the scientific community.
I have heard that many people do these things (declining offers already accepted) for academic positions, but that this is seen as much worse for postdocs positions. However, I think that everyone would agree that the second offer is a substantially better option, even the supervisor from the first university.
Should I give up the position I already accepted in order to pursue the better option?