The S.B.5 was built basically because the Royal Aircraft Establishment (RAE) Farnborough didn’t trust the configuration (mainly the low set tailplane) chosen by the English Electric company for their P.1A. This simple and spartan testbed proved the civil servant were the ones in error. Anyway, that waste apart, the manufacture of the S.B.5 turned out to be wise and profitable decision; it became one of most versatile and cos-effective research tool in highly swept wing surfaces thanks to its easily changeable wings.
Useful, but not pretty. The Shorts people obviously knew that and decided in this add to erase the S.B.5 fixed undercarriage.