Investing in silver miners hasn't been as profitable as betting on the white metal itself - but that's changing.

Actually, as a group, precious metals miners have been in a mutli-year downtrend. Take the case of the Global X Silver Miners (NYSE: SIL), the marquee ETF that tracks silver miners. Not only is that fund down about 21% year-to-date, it has tumbled more than 31% over the past two years.

That means with silver prices slated to rise, these silver miners are trading at a discount right now - very good news for anyone investing in silver stocks.

Here are three miners anyone investing in silver stocks should consider.

Investing in Silver Stocks: Cream of the Crop

For many industry followers, Silver Wheaton Corp. (NYSE: SLW) represents the top choice among silver miners.

Part of the reason for that is the company is not a miner in the traditional sense. Silver Wheaton provides financing to companies looking to expand or initiate mining projects. In return, Silver Wheaton gets a cut of the production at a fixed cost.

That means Silver Wheaton operates as a royalty-driven business, but still has more proven silver reserves than any other silver miner in the world. That is certainly an advantageous spot to be in, particularly if demand rises.

And that's exactly what has been happening in the silver mining industry this year.

"The mining industry is very, very hungry for capital right now and there are not a lot of sources out there," Silver Wheaton CEO Randy Smallwood told Bloomberg News.

In years' past it was the smaller miners that traditionally turned to Silver Wheaton when they were unable to gets funds from debt and equity markets. Now Smallwood says his company sees interest from the biggest producers in the industry.

"Companies more and more are looking to companies like Silver Wheaton to access funds to build their mines," David West, an analyst at Salman Partners Inc. who rates Silver Wheaton a "top pick," told Bloomberg earlier this year. "They have a great model."

Perhaps the best point regarding why silver investors should consider Silver Wheaton is the cost issue...