Hello to everyone.
I have been using a canon 50d for some years now. I do quite a bit of macro,portrait and close up work. I have been thing of upgrading to either the 7d 5d mark 2 or 3. I appreciate I will have to upgrade some of my ef-s lenses if I go to a full frame camera, but I am unceratin if full frame is going to be of any advantage to me and does come with a hefty price tag.
the question that i have for you are:
1. Does your jobs require the use of high ISO?
2. You do not use flash when being in a low light situation?
as if you answer "YES" in those both questions, then yes, you need a full frame. otherwise, you do not need it imo and it would safe you a hardship of trying to get rid of EF-S(s) for EF(s).
note: it does not mean that full frame requires understanding of light. imo, it is required to understand light when using every camera (including point and shoot). however, it is on you whether to learn it or not. but learning about light will give you a different way from taking pictures...