theres no advantage to them. they flex, they're heavier, massively susceptible to wind & very easy to break. I've broken 2 of them. If you only ever rode them on smooth roads they'd still break. the alu disc on the outside edge of the sheet rubs against the kevlar cord on the other side slowly wearing through the cord till it thins & the wheel looses all tension. Any decent rock will kill them instantly (if you live in a rocky area you'll know the dents onthe underside of your downtube from stones pinging off your front wheel, well they'll kill a disc drive
take a close look at tomacs bikes. his wheels were numbered (circled numbers near the rim), when they reached 20 (IE 20rides) they were binned.
deffo 1 of the greatest marketing retro ploys ever
(as a side note despite the fact they're utterly sh,te for actual riding I really miss the noise... & you havent heard a disk drive until you've heard 1 with a 91 hugi hub installed.. If you remeber Ned overend at the grundig world cup in plymouth you'll know what I'm talking about