Right now, there are investors out there thinking: "Sure, Sirius is risky. But hey, it only costs $7. I'll buy 100 shares and hope for the best. After all, with a price that cheap, what's the worst that can happen?

Answer: The same thing that can happen if you invest $700 in a company whose shares sell for $50 a pop. They could go up. They could go down. Or they could go really down, to zero.

In 1965, consumer advocate Ralph Nader wrote a book skewering the U.S. auto industry in general, and GM's (NYSE:GM) Chevrolet Corvair in particular, calling it Unsafe at Any Speed. In it, he highlighted a crucial problem with the car (a flawed suspension prone to catastrophic rollovers) that made the vehicle, well, unsafe at any speed.

Sirius Satellite (NASDAQ:SIRI) also has a single, critical flaw, making this investment unsafe at any price. Assume that Rick's 20 million subscribers are not a pipe dream. Assume it could happen. And assume that $7 is a low price to pay for the profits that Sirius could earn off of all those subscribers. Even taking all those assumptions at face value, how many of those 20 million subscribers will stick around after Sirius' uninsured satellites go kaput and the company doesn't have the cash to replace them? Zero.

And what will the company be worth when that happens? Also zero.

All it takes to cripple Sirius is for one satellite to break down. If two satellites break down, the company dies, taking your investment with it. If Sirius' management isn't going to -- or can't afford to -- insure the interests of its shareholders, you can't afford to own Sirius. At any price.

You're not done. This is just one part of a four-part Duel! Don't miss the Bull and Bear opening arguments and the Bull rebuttal. When you're done, vote and let us know who you think won this Duel. If you appreciate ultimate growth stock investing -- in companies just like Sirius -- you may want to give our Motley Fool Rule Breakers newsletter service a try.

Fool contributor Rich Smith owns no shares in any company mentioned in this article. The Fool has a disclosure policy.