I started a character on Stromm and went to sell some stuff in the Bazaar recently. While searching for some +INT items, I found a ton of these for 2-4pp. I picked up 2 at the cheapest traders (2pp each) and couldn't believe it! Other items with less +INT were going for hundreds of plat. The joys of playing on a newb server I guess.
Oh yes it is worth much more that 20pp. Look at the average price in the Bazaar. Either your friend didn't know the price or was possibly being very modest. :) I got lucky and found one for 2pp in the Bazaar...I have a feeling that the trader had left off a couple of zeros or perhaps thought she was selling a silver ring as opposed to a platinum ring.