Advantages/disadvantages of a double disc clutch setup

[180fan]

Ok, so I'm on the market for the HKS GD Max clutch kit, or OS Giken, or ORC 409 clutch kit. Double disc setups for all of them. However, I also have concerns about the following items.

1. typical life span of the clutch kits (these buggers are expensive, don't wanna be replacing the clutch discs every year)2. engagement3. pedal feel

I already know they can take a thrashing better than single discs. I've been told that they're also softer with the pedal, however, I'd prefer first hand info rather than second+ hand info.