My own research shows that CX4 is a much cheaper than Fiber in total cost of implementation.Originally Posted by netsyphon
With CX4 the transceiver is build into the switch. With Fiber the transceivers are a separate (and expensive) options, since there are different types of Fiber transceivers for different transmission distances.
Fiber is only better/cheaper in the actual cables; CX4 cables are more expensive and bulkier than Fiber.
Finally, most CX4 cables only supports connections to a maximum distance of about 20m (although Intel offers slim CX4 cables which support distances up to 100m)