Some products are hot. Others, on fire. Apple (NASDAQ:AAPL) has both, and that's not necessarily a good thing.

Early reports had a demo version of the Mac maker's new iPad Air sparking and exploding in a Vodafone store in Canberra, Australia. Mashable has since confirmed that the device in question was not, in fact, an Air but an older model iPad.

"It was an earlier generation iPad with Retina display model -- not one of the more recently launched devices. Apple is investigating the cause," a Vodafone Australia spokesperson told reporter Adario Strange.

That's good, right? Sure, but let's also remember that we're still talking about an Apple product exuding  a "burst of flames." Shoppers will rightly question what went wrong, and that ensuing investigation could crimp sales. A lot depends on the PR fallout.

Just ask Elon Musk. Tesla Motors has endured (count 'em) three Model S fires in recent weeks. Yet the backlash has proven minimal. Why? Owners are stepping up to defend Tesla. One even went so far as to claim his now-charred Model S saved his life. Apple may not be so lucky.

Sydney's Daily Telegraph newspaper reported that a fire brigade was called in after the Vodafone store filled with smoke. No one was injured in the incident, and Apple has since taken the device for investigation, the paper said.

More troubling is than the incident itself, I think, is the context. Apple endured criticism when tests revealed that the third-generation iPad ran significantly hotter than its predecessors. Why so hot? Speculation at the time suggested that a larger battery and power-hungry graphics created the conditions for overheating, especially when used for graphics-intensive gaming. Vodafone has yet to confirm which model iPad was engulfed in the fire.

Also, remember that Apple redesigned the battery pack for the Air. Two 32.9Wh cells versus three 42.5Wh cells in earlier-generation tablets, according to TechRepublic. The Air's more efficient design is said to require less power, which should mean less heat and fewer fireworks of the sort witnessed in Canberra.

Of course, we won't know more till Apple reveals the results of its tests (if it ever does). Should investors be concerned in the meantime? If we were talking about the Air, definitely. Since we're not -- and because we've known for more than a year that newer Retina iPads can be a scorcher -- there's little reason to believe this incident will take a toll on Apple's tablet sales.

Do you agree? Have you endured problems with a prior-generation Retina iPad? Leave a comment below to let us know where you stand.