I have looked at the design of the David Eyre hive on his web site (some time
ago so I am hazy on the details).  It shows his ex- pat Brit. history.  The
basic design appears to be based on the British National which, in spite of
having been designed by a committee, works very well and is used by about 80
per cent of UK beekeepers.
The innovation is the ventilation system which I have not tried but is on my
very long list of things to do.
Chris Slade