EMC went into unified storage long after rival , which still offers the most advanced unified technology, industry analysts say. Some critics have said EMC's VNX, with its two sets of microcode, is more a pair of systems, which come in one box and share a single management interface, than a true unified platform. VNX also still uses two applications, sold in a suite, for data replication. (They will be merged over time, EMC says.)

The company was forced to design VNX this way because it created the product out of two older platforms, Clariion and Celerra, says Forrester Research analyst Andrew Reichman. "You'd never choose to build that."

EMC counters that the dual-microcode approach is better than a fully unified system because if one part of the array fails, the other can keep working. But that capability has marginal value to users, says Enterprise Strategy Group analyst Mark Peters, who thinks NetApp's products match VNX for resiliency.

There's no mistaking EMC's seriousness about its new direction. It is discontinuing the Clariion and Celerra products. And for VNXe, the company is building a new sales channel. "They have committed themselves thoroughly to going down this integrated/unified route" and streamlining an overly complicated product lineup, Peters says.