My own experience with the Suplex rear shocks was not good. Could not get them to work at all at any preload and damping combination. When I was trying to get them to work I put the standard non-adjustable, worn out Spax shocks back on and found that they worked way better than the Suplex, I then went to the Spax adjustables on the back which worked well and then for other reasons went to Ohlins all round which works very well indeed.
The very early Suplex that were fitted as standard on the first few cars out of the factory may well have been very different.