interesting review. checked out online specs for the feisol before, was abit worried about the way it operates and the fact that it doesn't use normal arca swiss plates. glad someone took the trouble to handle one in person.
people looking for ballhead in this sort of range can also consider the kangrinpoche stuff. very similar to the markins, and even with some new ideas, like a smaller version, number markings on tension knob, and a new version with lever clamp quick release. cheaper than markins/acratech/arcaswiss models.