Elizabeth Harrow of Schaeffer’s Investment Research looks at one stock that’s a high flyer and another that’s trying to turn itself around.

[The Wall Street Journal’s Ahead of the Tape column recently took] a cautious look at Chipotle Mexican Grill (NYSE: CMG) ahead of earnings. Noting that the stock has "more than tripled since going public in 2006," and now trades "at about 22.5x estimated 2011 earnings," [writer Kelly Evans] says, "caution may be warranted" ahead of the burrito chain's quarterly report.

The company's habit of exceeding analysts' per-share profit expectations is a point of concern, says the article, because it means that hopes will be running high for another bottom-line beat. In short, concludes the author, Chipotle "will have to produce some spicy results" to disprove the skeptics. If the company can manage another stronger-than-expected report, though, there's still room for the stock to enjoy a boost as the remaining bears hit the exits.

For example, short interest accounts for nearly 9% of the equity's float, or roughly four days' worth of potential buying pressure. An upbeat quarterly report [may have prompted] a bout of short-covering, helping the shares to bounce back from their recent slump.

(It did beat expectations last week, and the stock soared, closing above $148 Tuesday—Editor.)

[Meanwhile, a recent article in MarketWatch by media columnist Jon Friedman] notes that Sirius XM Radio (Nasdaq: SIRI) is "getting serious," pun fully intended. The company rallied on news that net subscribers increased by 583,249 during the second quarter, reversing a year-ago loss.

"Perhaps now it is time for skeptics to rewrite their doom-ridden prognostications" for the satellite-radio business,” suggests [Friedman]. SIRI and its satellite radio services were viewed as an unnecessary luxury by many during the financial crisis and ensuing recession, but "with the economy showing signs of life, the industry could merit a fresh look," concludes this cautiously optimistic article.

If the author holds back from taking a truly bullish stance on SIRI, it's likely because the stock is still languishing just south of the $1 level. The equity has turned in a decent up trend in 2010, adding 66.5% year-to-date—and it's enjoying the reliable support of its ten-month moving average, which is more than can be said for the Standard & Poor’s 500 index (SPX).

Although SIRI has battled back admirably from its early 2009 flirtation with theoretical support at zero, penny stocks still don't command much respect on Wall Street. Despite its steady chug higher during the past year, SIRI probably won't win over too many critics until it rises beyond bargain-basement status. (It closed above $1 Tuesday—Editor.)

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