Sometimes the fear of pain is worse than the pain itself.

There are plenty of reasons that Advance Auto Parts (NYSE:AAP) might have sold off going into this quarter, but it seems like a lot of the worry was about the quarter itself. And though business is not exactly booming, fear might prove to be the long-term investor's friend here.

As I just said, this was a challenging quarter for the company. Sales were up a bit less than 11%, with 3.9% same-store growth (versus better than 9% a year ago). While the do-it-yourself business was even more of a laggard, with same-store sales up 0.5%, the do-it-for-me side was up more than 16% on a similar basis.

A lot of your common retail bugaboos were blamed for the result -- adverse weather, higher interest rates, and higher gas prices. Though I love nothing more than slamming retailers who offer feeble excuses for sluggish sales performance, I actually buy this story this time. You don't see a lot of Jaguar owners working on their car in the driveway, so I do believe it's entirely valid to think that higher interest rates (on credit cards, not just mortgages) and such could hurt the buying power of the company's core customers.

Margin performance was likewise not great, but not a horrorshow either. Gross margins were flat, and operating margins were down slightly, after adjusting for the added expense from stock compensation. And though talk is admittedly cheap, management continues to look to improve operating efficiency; it's still targeting margins of 11% to 12% by 2008 (as opposed to roughly 9.5% this quarter).

I've generally been a bigger fan of AutoZone (NYSE:AZO) than Advance Auto Parts (though I like both far more than I do Pep Boys (NYSE:PBY)). Advance Auto Parts won't be going on my wish list soon, even if it is undervalued. I mean, if interest rates and gas prices are problematic -- and aren't likely to get better any time soon -- why would I want to rush in and buy now? For folks with a longer-term orientation, though, the combination of improving margins, ongoing store renovation, and decent valuation might be a more appealing package.

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Fool contributor Stephen Simpson has no financial interest in any stocks mentioned (that means he's neither long nor short the shares).