If all else fails, and you're prepared to wipe the drive before an RMA, use Diskpart with the clean command. It's the best tool I know for screwed up partitions and GPT data on a drive.
OCZ's bad rep was deserved from the fast-and-loose Sandforce firmware issues, but those days are nearing a decade ago and we've been using Toshiba drives heavily (in quantities of several hundred) for a long time now.
Unlike Sandisk, Samsung, Hynix and Kingston I can safely say that Toshiba is the only brand that I have a large sample size with zero failures and zero RMAs across 1200 drive years of usage. Crucial seem to be making their way there too, but I've only been buying Crucial since the MX300 and I don't think I have 100 drive years tracked on the system yet.
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