Just one anecdote, but my parents used a friend to sell their house, and it was a complete disaster. The house sat on the market for six months despite being a red-hot market, they spent $25k on unnecessary repairs (the house was knocked down), the photographs/staging were atrocious (photos of a million dollar house taken by an ammeter with a cell phone), and there were big errors in the stats listed in the MLS.
My suggestion is to use your friend if they are the most qualified/best agent in the area, but chances are there's probably someone better out there.