The VTL gateways have GPFS inside.
When I last did an OS upgrade on an IBM VTL gateway, I was intrigued to see that the product is based on GPFS. (Sorry, I don't recall the specific model number.) For years I've wanted to kick the tires on a GPFS solutions, primarily to explore the HSM capabilities of GPFS and TSM on Linux.
For a while there, every other storage product that IBM brought to market was a flop. How many people remember or run SAN FS, as compared to SVC?