I'd get a new display, since you don't know how long the used ACD has been use for, the LCD may have lost much of its brightness, it may have color discrepancies, etc. Remember, the original ACD are a decade old product.
I am speaking with my 2 used ACD 20" displays. That said, I love ACDs, they are a breath taking design and look very very sharp aesthetically.
Im in the market for a monitor too, to plug in my 13". I was looking at AOC 23" led, at around 149$. Any thoughts on this one? I used to own one but it was 2 years ago and it was a 21.5" , maybe there are better screens out there at around this price range