I can answer questions if there are some
The red 9 kit is the only one available for the front that I am aware of at the moment. For me it was about getting a more compliant front end for improved braking with such a light front end and it does this. The kit I got needed some mods as clearance with the upper trailing arm was limited. Also, the rods that replace the torsion leaves stuck out and dug into the tyres on full lock so they have to be cut down once installed.
For the rear, purely dependant on vehicle weight and as mine is such a unique case I wouldn't like to give recommendations to others on spring rates etc. I used the 944 outer trailing arm covers for improved locaion after the loss of the torsion bars as they have a big supporting area.
Rich