Hmm....it depends on when you upgrade. Sometimes the anvil has her period and wont let you get anything pass +5...Sometimes she's horny and the more you put in, the better she gives <_<
Back in KE, i saved 9 mil (which was alot for me) and bought a priest impact for 8 mil. I was searching months for a cheap one and finally got it....then i burned that sucker reducing it at +1.
Oh the humanity