At The Motley Fool, we poke plenty of fun at Wall Street analysts and their endless cycle of upgrades, downgrades, and "initiating coverage at neutral." Here, we'll show you whether those bigwigs actually know what they're talking about. To help, we've enlisted Motley Fool CAPS to track the long-term performance of Wall Street's best and worst.

And speaking of the best ...
You love your Apple (Nasdaq: AAPL) iPad, but have you ever wished it was more like a MacBook? I mean, that virtual keyboard is kind of annoying. But what if there was a way to hitch a keyboard to your tablet -- not all the time, of course, but just long enough to write that pesky term paper or five-page memo for the boss? Well, now there is a way -- and according to Roth Capital, ZAGG (Nasdaq: ZAGG) is set to profit from it.

In an article earlier this month, my Foolish colleague Sarosh Nicholas told Fools all about ZAGG's latest and greatest add-on -- the Logitech Keyboard Case. You see, Apple came close to killing ZAGG's business model this year when it one-upped the company's ZAGGmate tablet protector with a new iPad Smart Cover. But rather than fade quietly into irrelevancy, ZAGG chose to recruit an ally and rejoin the fight. Collaborating with Logitech (Nasdaq: LOGI), the company developed an iPad cover that incorporates an actual, physical keyboard for typing into the iPad.

ZAGG's new case is winning rave reviews, and this week it also won a plug from the stock pickers at Roth Capital. Based in part on prospects for profit from this product, Roth recommended buying shares of ZAGG, and predicted the shares will fetch $12 apiece within a year's time. But is Roth right?

Let's go to the tape
It's hard to say for sure. In recent months, Roth has gone disconcertingly quiet on the website that aggregates ratings made public by Wall Street's analysts. That's a crying shame, because last time we checked, Roth's recommendations were actually doing pretty well at outperforming the market. While not all of its picks perform well, we have Roth pegged for 75% accuracy on picks it's made in the computers and peripherals industry.

Roth has made successful recommendations of companies including Hypercom and Netezza (a particularly prescient pick, as it was acquired last year by IBM (NYSE: IBM)). And it's not hard to see why the company likes ZAGG as well. After all, based on its GAAP financials, the company sells for less than 22 times earnings, yet is expected to grow those earnings at more than 26% per year over the next five years.

Right or wrong, Roth?
That certainly sounds good. But I have some reservations about this pick. First and foremost, it's been several months since Roth last made an appearance on CAPS with a fresh pick. Before following the analyst's lead, I'd really like to get a more up-to-date view on its latest thinking.

My second concern is ZAGG itself. While I admit the PEG ratio is tempting, and the Keyboard Case reviews certainly look encouraging, the thing that concerns me is that ZAGG has not yet shown itself capable of generating any level of dependable free cash flow from its business. Fact is, I'm probably more inclined to play the Keyboard Case phenomenon through ZAGG's partner on the project, Logitech.

Consider: With $113 million in annual free cash flow to its credit, Logitech is generating the kind of sustainable cash profits that it needs to remain in business and continue rewarding its shareholders. (ZAGG is not.) Logitech also has a long history of successfully piggybacking upon the success of hardware makers like Dell (Nasdaq: DELL) and Hewlett-Packard (NYSE: HPQ) by designing stylish peripherals to complement their products. It's even gone head-to-head with Microsoft (Nasdaq: MSFT) in the webcam wars, and survived.

Foolish takeaway
Mind you, I'm not saying I disagree with Roth's endorsement of ZAGG. I'm just saying that if Apple is showing a desire to keep profit from iPad peripherals for itself (and it is), then if I'm going to bet against it, and bet on a rival trying to piggyback on the iPad's success, I'd rather put my money on a company with proven staying power. So far, Logitech has shown it's got it. ZAGG has not.

Or at least, not yet. Do you think this stock's got what it takes to match Apple zig for ZAGG? Click over to Motley Fool CAPS now, and tell me why.