Source: ExxonMobil.

What: Shares of integrated oil and natural gas behemoth ExxonMobil (NYSE:XOM) moved fractionally higher by $0.06 to close at $91.56 on Monday despite receiving a rating downgrade from research firm Argus to "hold" from "buy."

So what: According to Michael Burke, the covering analyst for Argus, ExxonMobil has vastly outperformed its oil and natural gas sector peers over the past year. This is largely due to its diversified business that comprises upstream, downstream, and chemicals operations, as well as its relatively low levels of debt compared to its equity.

However, Burke believes that outperformance may be coming to a close, as he holds a bleak outlook regarding ExxonMobil's ability to grow its reserves and production. Burke worries that ExxonMobil may reach for growth via an acquisition, which is something that hasn't always worked out. Furthermore, Burke cites the company's plan to reduce its share repurchases to just $1 billion in the first quarter of 2015 from a prior average of $3 billion per quarter as a reason that shareholder sentiment may be negatively affected.

Now what: The $64,000 question that needs to be asked here is whether or not Argus' downgrade has merit. In others words, are you better off not buying ExxonMobil here?

In my personal opinion, I don't see much to fear if you're buying shares over the very long term, but I could certainly see merit in waiting out this drop in crude prices.

On one hand, there's no telling how low crude oil prices could go. Although recent commentary from OPEC has given this small rally in oil some legs, oil supply in the United States still remains high and total drill rig counts really haven't fallen by a substantial amount yet. We probably need to see some consolidation among the small and medium-size drillers and a significant shrinkage of rigs among large players before we can safely proclaim there to be a "bottom" in oil. In the meantime, it means ExxonMobil's revenue and profits will take a hit.

On the flip side, ExxonMobil has a smorgasbord of global assets to fall back on in spite of currently weak oil prices. It could temporarily have a hard time boosting production, but that's OK because long-term energy forecasts are on its side.

Energy outlook through 2040. Source: United Nations and ExxonMobil.

According to ExxonMobil's energy outlook through 2040, energy demand is projected to more than double to 1.2 quadrillion BTUs over the next 25 years. That bodes well for ExxonMobil, which is sitting on a number of onshore drilling opportunities in the U.S. and a handful of offshore deepwater finds off the coast of Africa.

In sum, I believe it's possible ExxonMobil could head lower over the short term, but would have no qualms about holding on to my shares or nibbling here if I had no intention of selling over the next five years.