Castle Creations motor and ESC combo recommendations for the Vanquish H10 Optic:

Copperhead 10 w/1406-2280kv on 2s or 3s - Good BEC for single servo. Will need external BEC if running rear steer or winch.
Mamba X w/1406-2850kv on 2s or 3s - A slight step up in wheel speed if you're a bit more aggressive driver.
Cobra 10 w/1406-2280kv on 2s or 3s - The gold standard of crawler setups. Hill Hold feature allows the motor to hold vehicles on a steeper incline than the normal drag brake would allow.

The 1406-2850kv paired with with the Cobra 10 X is also a good choice for 2s and 3s if you want a bit more wheel speed.

Always monitor ESC, motor and battery temperatures on new setups or when changing gearing or batteries.