Image source: Sirius XM.

It took nearly five months, but shares of Sirius XM Radio (NASDAQ:SIRI) finally closed at $4 yesterday. You have to go all the way back to the final trading day of 2015 to find the last time that Sirius XM wasn't trading below the $4 mark. 

The recent gains should stick, at least in theory. The satellite radio monopoly has never been in better shape. Its subscriber count topped 30 million in late March for the first time, and with average revenue per user moving higher as churn and subscriber acquisition costs hold steady, there's a real opportunity for this scalable operating model to deliver strong growth in the coming quarters.

The last time Sirius XM crawled out of the $3-and-change muck, it stuck around for a bit. Sirius XM closed at $4 or higher in all but one trading day during the final 10 weeks of last year. Then again, it's also had an even longer streak of staying under the $4 mark -- nearly five months -- that was finally snapped on Wednesday. 

There's more than one way to buy Sirius XM these days

Sirius XM has been one of the market's biggest winners since bottoming out at $0.05 -- yes, a nickel -- in early 2009. It's an 80-bagger in a little more than seven years, something you don't see very often. 

However, it's been a far less volatile satrad star that investors have been buying into these days. It has traded in a relatively narrow range over the past year as it does chin-ups above and below the $4 line. Its one-year beta clocks in at 0.96, a sign that its volatility has been in line with the blue chip-rich S&P 500.

This doesn't mean that there will be ups and downs, and something that majority stakeholder Liberty Media (NASDAQ:FWONA) did last month could result in more swings than what investors have been experiencing over the past year. Liberty Media completed a recapitalization last month, giving investors a few new ways to directly participate in Sirius XM's prospects. The media conglomerate spun off its stakes in Sirius XM -- as well as its ownership of Major League Baseball's Atlanta Braves -- into separate entities. 

There are now three classes of Liberty SiriusXM (NASDAQ:LSXMA) (NASDAQ:LSXMB) (NASDAQ:LSXMK) that let potential investors buy a tracking stock that is backed solely by Liberty Media's investment in Sirius XM. That's a pretty big deal since Liberty SiriusXM now accounts for roughly 63% of Sirius XM's outstanding stock. 

A new way to skin this cat may not seem to make Sirius XM volatile again in theory, and by bumping up the theoretical public float, it might even produce stability. However, the new stock will find institutional and retail investors weighing if Sirius XM or Liberty SiriusXM is the most effective way to cash in on the satellite radio revolution. Sirius XM investors may just be happy to see the stock hit a new year-to-date close, but the real goal is seeing if it can keep its head above the $4 mark as it aims for even higher ground. 

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.