Mining for Silver Stocks

I have been looking at three silver plays, which all hit 52-week highs today. The first one is Silver Standard Resources Inc. (SSRI). SSRI was mentioned in a Marketwatch.com article on March 11th as being a top newsletter pick. The other silver plays I am looking at is Silver Wheaton Corp (SLW) and Pan American Silver Corp.(PAAS). If I were to buy one of these stocks it would be Silver Wheaton Corp. But further research is needed.