I have the Leda's.
Currently I have the Oil set up with 325# front and 275# rear Leda springs.
The Oil set up is less harsh than the gas but I need adjust my spring rates for less lift off. Lift off is when your wheels leave the road due to hitting a bump or impact strip. The ride is OK and very sable at any speed.
The Gas set up with my Yoko A520's kept the car Nai!ed to the Road. I had Eibach 300# front springs with 250# rear. I had my corner weights balanced at 837.5 lbs on the rear and 1004.5 lbs on driver front and 948.5 lbs on passenger front with me in the car at 216 lbs and my 500 lbs sound system.
If I had the choice again I would get the gas set up and live with the loud noise over bumps.
I have not driven a car with Koni's. TrueChoice does a shorten Koni with Ground Control threaded sleeve to give you the same travel you get with a Leda. To get that Koni set up you will be paying more than the Leda gas set up. With the un-shortened Koni you can't lower your car without hitting the bump stops routinely due to reduce travel in the strut of a lowered car.
Enough words, Let me stop now

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