Hong, going back a few posts a cushioned clutch has nothing to do with a sprug center rather a cushioning between each side of the clutch plates. A conventional button uses a single sheet of metal with puck either adhered or riveted to it. The Cushioned plates use two plates with a "spring" in-between. This "spring" takes the initial shock of the engagement rather then other driveline components such as gearboxes and diffs
Bacially if the vehicle is mainly a daily driver, and a puck clutch is your preference, I would strongly suggest using a cushioned item.
The sprung center is purely a sound/vibration dampener.
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