The tremendous popularity of the 1975 Convoy song by C.W. McCall depicting droll conversation among CB-communicating truckers put several phrases, such as 10-4 for "understood" and what's your twenty? (10-20) for "where are you?"
"5 sur 5" sounds a little outdated to me (well maybe that's just me ^^), but I think everyone would understand itIt must be a technical term--it's not widely used, in AE anyway.
La tournure 5 sur 5 est-elle largement comprise en français ?