I finally had the time to test the "active rear suspension" conversion. You know I was sceptical, but it works! On my first run I could already better my personal lap record by two hundreth from 12.64s to 12.62s. It makes the car turn better without giving oversteer. Combined with some small setup changes (long rear camber links and RSD TC6.2 springs white in the rear and light blue in front), I could reduce my personal best to 12.39s.
So from my point of view I can recommend the conversion.
My 6.2 ran 17.5t blinky with VTEC G32 tires on a medium grip asphalt track.
@Christian: You should find someone who sells your awesome products in Germany