Hi mick
Regarding brixl: a 2.4ghz remote control system, especially targetting truck and construction type of modelltruckers.
Its popular in the german speaking market, since no english version is available :-/
http://www.brixlelektronik.de/sender.htm
Swapping esc is straight forward, done it several times. And if you dont want to keep the mf unit, you can replace it with servonaut ml4 or a modul from beier: containing sound and multiswitch:
http://www.beier-electronic.de/modellbau/ called usm-rc2.
Br,
Thomas