I don't know how it compares with the DJI F450.
This was designed from a high resolution picture of my original top plate. It should be perfectly symmetric.
I cut it in a 1mm thick aluminum sheet and it makes a great replacement for the original fiberglass top plate that I broke when I crashed my quad.
The details of the quadcopter build are at
The additional four holes are to mount a multiwii flight controller like the hobbyking 328p, with 45mm spacing between mounting holes.