I adapted the 'home made' one on the Stapely & put it on a sliding base so it can be adjusted for different drivers leg length as we tend to pass boats around trusted folk in the CMBA.
I bought a brand new 'Hot Foot' at Beaulieu last year for £40.00 so that is going on the base plate instead now. At the moment when a short driver gets in the shockcord doesn't always close the throttle fully!