many mfgrs just repackage drives that have been shipped in for RMA's after they ahve been unlocked/recovered. Sandforce drives havewhat's called a panic locked state for which RMA is necessary. All that's required by the mfgr is to use an engineering flash to release the locked state and restore full performance. Drives are also updated to the latest firmware as well during the process.
Thing to remember is that locked drives are usually the result of bios incompatibility/sleep transition issues and NOT due to users pounding them with data or numerous benchmarks or any sort of abuse. I would say you have a decent drive that should be fine for many years. Well.. assuming you don't panic lock it again from your end, right? lol
Hope that helped.