We also use our pot filler as a faster drinking water faucet (filtered), so water doesn't sit in the pipes for long. Also, if boiled, it doesn't matter if it sits in the pipe for a while. Agree with measuring position based on your tallest stock pot, at least, and with access to your strongest burner. Ours is hung at a generous height of 18" (burner surface to filler outlet) and centered when folded back on our 36" stovetop for aesthetics and access to all burners (all but one burner are the same output rating). I recommend covering the most burners possible (near the 4 adjoining burners), if they are all rated the same. We use ours all the time.
Q