Cronos Group (NASDAQ:CRON) and MedMen (OTC:MMNFF) are partners. And they've both experienced a very eventful 2018. Cronos Group's share price has soared more than MedMen's has this year. But MedMen's market cap has grown more. The company's issuance of new stock, however, caused enough dilution to offset its share-price gains.

Which of these two marijuana stocks is the better pick heading into 2019? Here's how Cronos and MedMen stack up against each other.

Marijuana plant hanging on globe over North America

Image source: Getty Images.

The case for Cronos Group

Cronos Group isn't just one of the best-performing marijuana stocks of 2018; it's also the best-performing marijuana stock of all time. And there's a pretty good argument to be made that Cronos Group's prospects are brighter now than they've ever been.

The main reason why is Cronos Group's recently announced deal with Altria (NYSE:MO). The big tobacco company is buying a 45% stake in Cronos for around $1.8 billion. Altria also has an option to gain a majority interest in Cronos in the future.

There are several huge benefits for Cronos from the transaction. Gaining a nice chunk of cash definitely helps. The company already has some ideas on how it plans to invest the money to fuel growth. It should also be very helpful for Cronos to have a partner at its side with decades of experience in navigating highly regulated markets across the world.

While Cronos Group's relationship with Altria puts it in a better competitive position than in the past, the company's opportunities are also expanding. Cronos was already established in the Canadian medical marijuana market. It should enjoy significant growth as the country's recreational marijuana market gains momentum.

Cronos is already active in Germany, Poland, and Latin America. More markets are opening across the world. The United Kingdom moved to legalize medical cannabis earlier this year. South Korea followed suit just a few weeks ago. Mexico could soon legalize recreational marijuana.

And Cronos could even get a break in the U.S. Although marijuana remains illegal at the federal level, the 2018 Farm Bill makes hemp -- which is cannabis that contains low levels of psychoactive ingredient THC -- legal throughout the country. This could open the door for Cronos Group and Altria to develop hemp-based products for the U.S. market.

The case for MedMen

You could probably argue that MedMen's prospects look better than ever, too. While MedMen hasn't been sought after by a tobacco giant like Cronos Group has, the company has made some big deals of its own.

In October, MedMen announced that it planned to acquire PharmaCann. MedMen CEO Adam Bierman called the deal "a transformative acquisition that will create the largest U.S. cannabis company in the world's largest cannabis market." Bierman was right.

After the transaction closes, MedMen will have cannabis licenses in 12 states that give it the rights to operate up to 79 cannabis facilities -- 66 retail locations and 13 cultivation/production facilities. MedMen already operates retail cannabis stores in California, Nevada, and New York. It acquired businesses in Arizona and Florida as well. The PharmaCann deal will give the company a presence in Illinois, Maryland, Massachusetts, Michigan, Ohio, Pennsylvania, and Virginia.

MedMen's sweet spot, for now, is in California, where recreational marijuana is legal. Its stores there rank very highly in sales per square foot -- beating some well-known retailers on the key metric. But Nevada has a thriving recreational marijuana market, too. And with the acquisition of PharmaCann, MedMen will compete in Massachusetts and Michigan, both of which have legalized recreational marijuana, plus Illinois, which could be on the way to doing the same.

There's one number to keep in mind with MedMen: $40 billion. That's the projected size of the addressable market the company could see by 2030 in the states where it will operate once the PharmaCann transaction is completed.

Don't forget MedMen's Canada connection, either. The company teamed up with Cronos Group to launch retail stores throughout Canada. 

Better marijuana stock

Both Cronos Group and MedMen have great opportunities before them. However, I think the nod goes to Cronos Group as the better marijuana stock right now.

While both of these companies have issued a lot of new shares to raise cash in the past, my hunch is that MedMen will keep doing so at a faster pace than Cronos will. That's especially the case now with Altria owning nearly half of Cronos Group. The tobacco giant probably isn't going to want to see its stake diluted. 

That doesn't mean that Cronos won't have some challenges. It wouldn't be surprising for its stock to remain very volatile. I like the company's long-term prospects, though, and fully expect Altria to gain majority control in the not-too-distant future.