From the mid-50s, a less performant but more reliable machine based on the Manchester Mark 1 - the Metrovick 950, from Metropolitan-Vickers, part of AEI (in the UK). Some half dozen were made, and two were sold. There’s a personal account of the machine in the Computer Conservation Society’s magazine, Resurrection, from which the photo below is taken:
I will start by telling you how I got involved with computers and, tied in to this, why Metrovick/AEI got involved. I will go on to describe the development of the Metrovick 950 followed by the AEI 1010. Finally, I will describe a particular 1010 installation.
via this Q&A: