I have those you referenced on my SPIII.
They weigh a ton, each, rust, the surfaces are heavily pitted and just found this week 2 huge radial cracks in one disc.
They squeal horribly with standard pads. The surface just glazed up. I am using a. Sintered pad which greatly improved stopping, stopped squealing and not obvious differences in wear rates.
The discs are 5 years old and have done 50000km with winter riding also.
Adam