These OC appliances are deployed in ISP racks, and based on the specs they A) aren't cheap to make and B) are probably 4U based on the support of 44 SATA SSD's.

These OC appliances are deployed in ISP racks, and based on the specs they A) aren't cheap to make and B) are probably 4U based on the support of 44 SATA SSD's. I don't work for Netflix or an ISP, but part of the goal is to probably reduce the total expense (since they just GIVE these to ISP's who have enough Netflix traffic) as well as minimize the footprint. A single 100Gbe connection could easily plug right into an ISP's core router or distribution switch and take up minimal space in a datacenter, but you'd need to eat 3 40Gbe ports to get the same performance and X*2U amount of extra rack space to give a horizontal solution.