I found it great for feathering out and getting a good edge but it became really smooth and had a few adhesion issues with even lo-tac tape pulling the paint off, I should have used some zinneser on those areas first.
will still use fine filler but do the above next time!
Not aware of anything like a high build auto primer. You can use a fine filler (Toupret do one) but it can cause some issues.