I told my GG the other day, "Do you know normally guys spent 2 month salary on engagement ring?" he said, "Oh, I heard it was 3-month salary",

then I said, "Oh, in that case, let's use ur standard". :P

I like this ring, but still think Tiffany is a little pricey, BTW, my co-worker just bought his girlfriend a diamond ring from Hong Kong, it's much cheaper to buy it in Hong Kong, first because there's no sales tax on it, also because competition is fierce in HK. So maybe you could talk with your GG about this. :)