Lots of familiar stuff on that Speedplay page.
My framebuilder (Frezoni) has a set of the Cinelli clipless pedals, one of the later versions from memory.
I raced on an early set of Keywin clipless pedals and was happy to swap to a later version that were easier to clip into.
I think Berto was a big fan of the CycleBinding clipless pedals but I never saw them in the flesh.
Lots of those Look 'racing' black pedals broke, we warranteed quite a few of them.
A mate had a set of the MKS clipless pedals and only retired them when he ran out of cleats.
The Campag SGR pedals were beautiful and about the most adjustable pedal ever but no racer used them. The set we had at the shop ended up on a steel Colnago, of course.
The Adidas clipless pedals were popular with trackies (couldn't pull a foot) but roadies stayed away.
The Foster aluminium Look cleats wore the pedals into dust instead.
The SR pedals worked ok but the cleats were so tall that they were impossible to walk in, even into a cafe.
I remember seeing the Time TBT pedals on the French team bikes at the prologue of the 1987 Tour Feminine and not knowing what they were.
Our shop had a set of Mavic Look pedals for years as the plastic appearance put off the punters.
I think we had a pair of Primax pedals that didn't shift too, despite deep discounting. Replacement cleats for orphans was always a problem.
A friend mourned his Time TWT pedals when there were no more cleats to be found.
The set of Diadora pedals ended up being used by the shop owner as the market were locked onto Look or Time only.
The Performance pedals were made by Wellgo and also sold under their own name. They were remarkably cheap, worked pretty well and were popular enough until the cleat supply dried up and Look pedals dropped in price.
Mag Flux pedals always collected magnetic dirt particles which wore the body and cleat interface away. Who could have guessed that would happen?