I received my VrBrain4.5 order today. I used an APM2 on a SpiderLike Quad and I just swapped the two units on the frame. As I had a spare 3DR uBlox GPS, I managed to install it with the VrBrain (internal plug).
Firmware is the latest dev VRBRAIN_3.1.5_QUAD_INTGPS_ENHANCED.dfu.
I had a short flight to check my setup before dinner and i'm quite happy with my new setup.
Here are two pictures (there is a 6" ruler on the frame).
Frame is home made.
R/C setup: Futaba T14SG transmitter, Frsky TRF4 PPMSum receiver (8 channels).
VrBrain box is installed on 4 moon gel pads.
VrBrain box came with 4mm metal screws. I tapped the holes with a 3mm tap and used short nylon screws to close the box. No risk of breaking the holes, nor magnetic interference.