"Don't catch a falling knife," as the old saw commands. (Pardon my mixing a cutlery metaphor.) The idea of buying a former superstar stock at a discount price certainly has its attractions, but you've got to make sure you catch the haft -- not the blade. That's where Motley Fool CAPS comes in.

Today, we once again stand beneath Mr. Market's silverware drawer, measuring which knives have fallen the farthest. Then we'll call on CAPS to ask which of these stocks -- if any -- Foolish investors believe are ready for a rebound. Let's meet today's list of contenders, drawn from the latest "52 Week Low" list at Nasdaq.com:

52-Week High

Currently Fetching

CAPS Rating (out of 5):

Delek U.S. Holdings  (NYSE: DK)

$30.77

$12.32

*****

Orthofix International  (Nasdaq: OFIX)

$61.66

$30.21

*****

Riverbed Technology (Nasdaq: RVBD)

$52.81

$12.86

***

First Horizon National  (NYSE: FHN)

$41.46

$13.63

**

FirstFed Financial  (NYSE: FED)

$66.95

$24.66

*

Companies are selected from the "NASDAQ 52 Week Low" list published on Nasdaq.com on the Saturday following close of trading last week. 52-week high and current pricing provided by Yahoo! Finance. CAPS ratings from Motley Fool CAPS.

Knives and knaves
If there's one good thing about a broad-based market sell-off, it's that you find a lot of terrific companies getting the ol' baby 'n' bathwater treatment. Tossed out on their rosy little bums as if they were bums of another sort. You just know that some of these babies are gonna bounce right back once the suds subside.

Two such stocks appear to have washed up on our list this week: Five-starred Orthofix International and Delek U.S. Holdings. Of the two, though, CAPS investors seem to prefer Delek; twice as many investors have rated the Israeli-owned, U.S.-based oil refiner as have taken an interest in the orthopedics manufacturer. So let's see what all the fuss is about, as we examine ...

The bull case for Delek U.S. Holdings
We'll start with an introduction to the company, courtesy of CAPS All-Star RioRRawGnIkIv:

Delek is an [Israeli]-held refiner in Oklahoma -- it's production is optimized for Diesel fuel (low-margin gasoline is a by-product)." In this, Delek seems to differ from, say, Valero (NYSE: VLO) or Tesoro (NYSE: TSO), two refiners who are much more closely identified with the gasoline trade. RioRRawGnIkIv continues: "[They] own a growing (by acquisition) chain of Truck-stop / convenience stores for Vertical Integration ... They are NOT dependent on Imported Oil -- all their Oil comes from Oklahoma under Long-term Mutually Beneficial supply Contrxcts.

In January, fellow All-Star tenmiles opined that: "Delek appears relatively cheap here, both on a market basis as well on peer universe comparisons (UPL, MUR). ... above average potential for patient longs at $17." So you gotta figure tenmiles loves the stock at today's price of $12 and change. (In fairness, RioRRawGnIkIv is also underwater on this one.)

Perhaps our All-Stars would have been wise to listen to non All-Star SOFTrader, who suggested back in November that it was: "Not a good time to be in this stock now with the oil prices constantly setting new records. Once oil prices stabilize or drop a little, I think this stock is going to show some life." Then again, maybe SOFTrader should have heeded his own advice. Yes, you guessed it -- SOFTrader, too, is on the losing end of this trade.

Sadly for all concerned, oil prices remain volatile today. The good news, however, is that at least Delek's price looks more attractive. The stock trades for less than seven times trailing earnings, yet analysts expect Delek to grow its profits at nearly 10% per year over the next five years. That gives this crude-cracker a mouthwatering, if slightly oily, 0.7 PEG ratio. That looks cheap to me -- but then again, wiser Fools than I have thought much the same about Delek in the past, only to get tripped up on the trade. Tread warily.

Time to chime in
Of course, the aim of this column isn't just to tell you what I think about Delek U.S. Holdings -- or even what other CAPS players are saying. We really want to hear your thoughts. Click on over to Motley Fool CAPS and tell us what you think.

Motley Fool CAPS: It's fun, it's free, and it just might make you famous.

Fool contributor Rich Smith does not own shares of any company named above. You can find him on CAPS, publicly pontificating under the handle TMFDitty, where he's currently ranked No. 863 out of more than 95,000 players. First Horizon is a Motley Fool Income Investor pick. The Fool has a disclosure policy.