Guys, i need your help.

I am planning to upgrade my esc/motor for my 1/10 scale HPI Bullet Flux MT monster truck which weighs abt 2.8kg.
I have 2 plans and need your help to find out which will be the best option for my esc/motor combi.

1) To buy a Castle Creations 1/8 2200kV Sidewinder 8th Brushless System (Both ESC and Motor)
2) To use my existing 4000kV HPI FLUX MMH-4000KV BRUSHLESS MOTOR with either one of these ESCs:

- Castle Creations 1/10 Mamba Max Pro ESC Smart Sense
- Castle Creations 1/8 Mamba Monster 2 Waterproof ESC

HPI Motor specs:
4000kV Sensorless Brushless 4-Pole 1/10th Scale Motor
3.2mm Shaft
4mm bullet connectors


I like bashing and speed.
Please advice. I am new to this. Thank you