Yep ... the Kontronik Jazz 55-10-32 ESC has proportional brake. Two car modes. One with reverse and the other is forward only.
This is my latest truggy (11lbs) video from today: Neu 1515/2Y (1100KV), Jazz 55, 10s1p A123 with proline badland tires: up to 2KW on this run. With a little heatsink on top of the cooling plate it runs cool and my highest peaks reached 100-120A (max of my eagletree micropower v1).
Good luck with you project ... looks very promising.