Cheers guys.
Brushless weapon motor is actually something I didn't consider and I think its a great idea. Going to look into it after the champs.

Brief summery of Whitwick was that it started bad and performed better as the event progressed. The RX slid out of its mount twice so caked it in hot glue and that seems to have kept it still.
The drive had a moment fault but it was to do with the tensioner so planning something better
Its solid enough. Was flipped by the arena flipper twice which had the power to launch it up to the ceiling and land on the other side of the arena 5ft up on the polycarb wall.
On one of its arena flipper voyages the weapon motor cracked which isn't a surprise. So planning a more resilient weapon motor.

Currently it needs to shave weight and it has completely been stripped down and all parts weighed. Very confident it will be in weight.