Hmm things which are not just a feeling: * Confidence in interoperability / drop in replacement * Can use existing configuration(s) without rewriting * Can b

Hmm things which are not just a feeling: * Confidence in interoperability / drop in replacement * Can use existing configuration(s) without rewriting * Can benefit from existing knowledge, training, expertise and documentation * Service, existing contracts, etc. * Network architects / designers don't have to find new visio stencils (Ok joking... well, half joking). TL:DR; I think most customers in Cisco are buying into the ecosystem, not the hardware.