You may be getting a bit more than you paid for with some of the latest MacBook Air notebook units.
Per AnandTech, Apple eventually included a commercially available Toshiba Blade X-gale solid state drive module, model TS128C with the notebook.
Reports have surfaced showing MacBook Airs equipped with a second, even faster SSD with a SM128C part number — the “SM” hinting at its presumed Samsung manufacturing origins. Samsung’s SSD manages up to 260MBps read and 210MBps write speeds compared to Toshiba’s 210MBps read and 185MBps write performance. While it’s hardly unusual for Apple to multi-source components, aa recent decision to source parts from Korea’s Samsung would have been a smart move to keep just-in-time supply lines fully stocked following the spate of disasters in Toshiba’s home country of Japan. Unfortunately, there doesn’t appear to be any way of confirming which SSD you’re about to purchase without cracking open the retail box and running the OS X System Profiler…
To sum it up, you might get a bit luckier than you expected when snagging the current MacBook Air, it’s just a matter of chance.