Student or Learner
You think about breaking up with your girl-friend. So you give her a call and say, "I was going to say this to you. I don't think we should see each other anymore." How often would we use a perfect form of "going to"? "I've been going to say this to you?
And this would be one of those appropriate contexts. There is the usual past simple/present perfect difference:
"I was going to say this to you last week (but I didn't)."
"I have been going to say this to you for some time, (and now I am saying it)."