I have mine, While waiting for the chance to start cfi, ($$$)
I am able to teach ground, get more experience and be more confident with learning styles. Keeps you from getting stagnant.
I am working on the IGI currently.
If you are working on cfi now and expect to have it soon, I just may not bother with it
The AGI exam is very much like the CFI written, it might help you get a better score for the exam that really counts