We really like PCMark 7's Secondary Storage benchmark module for its pseudo real-world application measurement approach to testing. PCMark 7 offers a trace-based measurement of system response times under various scripted workloads of traditional client / desktop system operation. From simple application start-up performance, to data streaming from a drive in a game engine, and video editing with Windows Movie Maker, we feel more comfortable that these tests reasonably illustrate the performance profile of SSDs in an end-user / consumer PC usage model, more so than a purely synthetic transfer test.
It does't get much closer than that! The Samsung SSD 960 Pro is highest performing drive we have tested with PCMark's trace-based benchmarks, and the Toshiba XG5 came in just a single point shy of the 960 Pro. If you look at the individual tests, the XG5 trailed the 960 Pro by a couple of MB/s in a few tests, but pulled ahead in the Importing Pictures benchmark, which helped boost its overall score here.