They are both amazing monitors, you can't go wrong no matter what you choose. my only complaint is the price on the BenQ, i went back and forth between these two when i was looking for a new monitor, i went with the VG248QE and love it!
Another bonus with the VG248QE is if you are interested in G-sync they sell a DIY kit for the VG248QE, IMO the kit is priced a bit high right now but as you see more G-sync monitors the prices should drop.
which display will have better colours??