Kamerar Follow Focuses and cages

What do you think about Kamerar FF-3 Follow focus and Kamerar Tank TK-2 Cage? Is there anybody knows them, how are their built quality and are they durable?
This is follow focus: http://kamerar.com/products/kamerar-ff- ... rods-clamp
This is cage: http://kamerar.com/products/kamerar-tan ... ds-support
This is follow focus: http://kamerar.com/products/kamerar-ff- ... rods-clamp
This is cage: http://kamerar.com/products/kamerar-tan ... ds-support