I am hereby selling my HPA scorpion due to switching to GBB.
It shoots straight and exactly where your dot is.
The trigger board settings aren't quite right, but I personally don't have the expertise to get them perfect. The replica works fine otherwise.
It is pictured with a vertical grip, but I am offering it for sale without a grip so it fits perfectly in the accompanying bag.
For questions, more photos, or a video of the replica, please feel free to send a message!