Just as a follow up, I took both Sovs into the local coin dealer. She grades quite conservatively. She got the eye loupe out and tilted the coin this way and that carefully taking her time. The 1884m shield graded good EF for the obverse and UNC for the reverse. The hair near the eyebrow has some very slight wear.
The 1879m St George apparently has been cleaned
It graded EF for the obverse and almost UNC for the reverse. A little disappointing since it was advertised as UNC. Not that I paid anywhere near that much for it. I still got my money's worth.
Both are obviously very nice still, but could be better. FYI the 1879m St George with medium tail on the horse has a book value of $2000 AUD for a true UNC.
She said I got a bargain if I paid anything less than AUD $320 for the shield so at AUD $219 I guess I did.