Comparing elliptic curves over prime fields against EC over binary fields In which scenarios we go for prime fields or binary fields? Please indicate why we would choose one over the other.
Binary fields were developed since they yield more efficient implementations. This is especially true given the Intel PCLMULQDQ instruction. Note, that there are special types of Binary fields that are even more efficient, like Koblitz curves.

However, in general, our confidence in the security of these curves is less than for prime-field curves. Thus, in general, my preference is to use prime-field curves unless there's a special reason why not to.