Plug Power (PLUG 10.20%) stock has been a roller coaster. In January, shares nearly doubled in value only to give up those gains by the end of the month. February brought much of the same, with the stock price recently surging 17% over a handful of days. Despite the volatility, shares remain well below their all-time highs. But if the company's management team succeeds with their vision, it's possible that Plug Power stock could rise in value by 1,000% or more. Is this beaten-down growth stock finally a buy ...