I'm a PhD student in my third year (4-6 is common in my country) and seriously consider abandoning my current topic. The new topic is in the same general field (CS related), yet in a vastly different domain and would need a quite different methods. My advisor suggested this switch, he could keep me funded in both cases, yet probably better with the new topic.
Arguments for switching are both personal interest in the new topic (it's recently trending, I was interested from the beginning, yet few positions were available) and lack of progress in the current area:
I could produce some publications, yet not up to my advisors expectations (should be easier with the new topic, given the impact factors of the journals my advisor suggested)
For the last 6-8 month I made barely any progress (lots of failed experiments)
I would probably have to abandon my current methods anyway due to 1./2., so half a year or so will be lost learning new methods no matter how I decide
Yet I shy away from switching, mainly due to already being quite old (combination of personal problems and a switch of my major as an undergraduate) and fearing how my C.V. would look if I did take about a year longer and had this second switch...
Thanks for any input.