There is a wonderful 3 page ‘thumbnail’ flight test report on the Spearfish in Eric ‘Winkle’ Brown’s book Wings of the Wierd and Wonderful volume 1.

In which he states tht before hydaulic airlerons were fited: ‘The Spearfish had heavy controls in cruising flight and in fact the lateral control was so solid I could barely move the ailerons with one hand at 150mph.’

Hope this helps Steve.