The rally since the beginning of the year has been more or less unrelenting, with more than 1,100 companies currently trading within 5% of their 52-week highs. For optimists, these rallies may seem like a dream come true. For skeptics like me, they're opportunities to see whether these companies have earned their current valuations.

Keep in mind that some companies deserve their current valuations. Nothing is a more hot-button issue than whether Apple (Nasdaq: AAPL) can keep up its torrid growth pace as its valuation approaches $600 billion. With a newly instituted $2.65 quarterly dividend, a $10 billion share-repurchase program, and more than 3 million new iPads sold in the first three days of release, it's hard to argue against owning Apple.

Still, other companies might deserve a kick in the pants. Here's a look at three companies that could be worth selling.

Not quite a banner year
Much of the banking sector finally appears to be on the mend, though some banks have further to go than others. Bank of America (NYSE: BAC), a symbol of financing malfeasance throughout much of the recession, looks to be on the cusp of putting its foreclosure settlements in the rearview mirror. But the smaller regional banks are still leaving a lot to be desired despite the turnaround.

One such company is Banner Bank (Nasdaq: BANR), out in my home state of Washington. The company has reported three straight profitable quarters, reduced its loan portfolio's reliance on single-family home loans, and cut its loan-loss reserves in half year over year. What's not to like, you might wonder? How about the fact that Banner still needs to repay TARP the $124 million it borrowed, and I simply don't see that happening without a dilutive share offering. I'm also not convinced that Banner has rid itself of enough non-performing assets. With the stock trading for right around book value and numerous other banks trading well below book, it's an easy trade-off to bypass Banner at these levels.

Finally, a natural gas sell candidate
I may be one of the biggest natural gas bulls of late, but even I draw the line at Clean Energy Fuels (Nasdaq: CLNE). I think investing in natural gas fueling stations at this point in time is brutally premature. There's also the fact that I'd prefer to invest in companies turning a profit -- something that Clean Energy Fuels and its 257 CNG and LNG stations cannot currently say.

The truly damaging news this past week came from a combination of General Electric and Chesapeake Energy, which are teaming up to create 250 CNG fueling stations around the country, as reported by the Fool's own Travis Hoium. The market for CNG vehicles is still in its infancy, and another competitor is the last thing this company needed. I'm switching the nozzle to "off" on Clean Energy Fuels.

I admit that I'm just not a fan of golf, and that makes it easy for me to pick on Callaway Golf (NYSE: ELY).

The maker of golf-related equipment has been in what seems like a continuous downward spiral since the recession. Callaway has missed Wall Street's earnings estimates in three of the past four quarters, and its losses have widened as a result of a business restructuring. If that's not enough, the company also recently went through a CEO change. It's incredibly tough to trust Callaway's turnaround when peers Nike and Under Armour are having no problem garnering new customers and getting top-notch ambassadors under their belt. Buying Callaway after its recent performance is like aiming directly at the bunker. Thanks, but no, thanks!

Foolish roundup
This is what I call a "prove it" week! These three companies have high expectations built into their stock prices, and I say you make them all prove their worth before you buy. I'm so confident in my three calls that I plan to make a CAPScall of underperform on each one. The question now is: Would you do the same?

Share your thoughts in the comments section below, and consider using the following links to add these three stocks to your free and personalized Watchlist so you can keep track of the latest news on each company. And to avoid investing in stocks like these, consider getting a copy of our special report, "The Motley Fool's Top Stock for 2012." In it, our chief investment officer details a play he dubbed the "Costco of Latin America." Best of all, this report is free for a limited time, so don't miss out!