Shares of Plug Power (NASDAQ:PLUG) are up yet again today, after the fuel-cell company that many investors see as a play in electric vehicles garnered massive returns, and showed investors an unbelievably volatile ride during the past year. Today's gains were on the news that the company would be buying ReliOn, a fuel-cell technology company, in a $4 million all-stock deal.

In this segment of Thursday's Investor Beat, host Chris Hill and Motley Fool analyst Jason Moser take a look at the performance of Plug Power's stock during the past couple years. While he sees the acquisition using all stock as incredibly smart by management considering how expensive the stock is today, he sees the dilutive event as one that should give investors some concern. With the company at 40 times sales today, Jason sees this one as incredibly expensive, and one that he'll be watching from the sidelines.

Chris Hill has no position in any stocks mentioned. Jason Moser has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.