These should sound exactly the same as the corresponding KM 100- or KM 180-series mikes. But the capsules are somewhat less expensive than the "active capsules" of the KM 100 series, because the Schoeps patent has run out, so Neumann (and parent company Sennheiser) are now free to build active accessories without having to put FET circuitry in the capsules any more to work around the patent.
There is no special resemblance to the older fet 80 microphones such as the KM 84--that's a total misimpression there, I'm afraid.
--best regards