Does anyone have any real experience with using prototype screw couplers (eg the type that come with the 5610 set) on 1 gauge rolling stock in terms of minimum radius? I'm thinking of using the prototype couplers on some 1 gauge modules and wondering what radii are possible with them.

I know the Marklin literature recommends 2.10 or 2.30m radii for prototype couplers, but there is also a Marklin Magazine article from 2004 that states that 1.55 to 1.60m radius works with wagons shorter that 40cm using prototype couplers. Anyone tried different radii with prototype coupler?

Richard