I've said it before, and I'll say it again: Board the lululemon athletica (Nasdaq: LULU) train now and buckle in for the long haul. This high-speed train is moving so fast that getting off before you reach the final destination may be detrimental to your portfolio.

The yoga highflier is raising its guidance for the current quarter amid strong holiday sales, brought to you by the polarizing inventory buildup that's been the subject of debate lately. lululemon now expects revenue in the fourth quarter to be between $358 million and $363 million, up from the prior range of $327 million to $332 million.

Diluted earnings per share should be in the ballpark of $0.47 to $0.49, compared with the previous guidance of $0.40 to $0.42. Comparable-store sales on a constant dollar basis are expected in the low-to-mid 20s, better than the low-to-mid teens guided during last quarter's results.

Further vindicating the apparel maker is CEO Christine Day's comment: "Our work throughout the year building our inventory position is driving our success in the fourth quarter. Guests have responded exceptionally well to the robust assortment and bright color palette for holiday, and momentum continues with the new spring product offerings."

Remember when I said, after the latest earnings release, "I'm not concerned about the inventory, since I expect all those luon Astro Pants to get a move on once the holidays roll around"? Well, the bumped-up guidance speaks for itself.

The figures also handily top analyst consensus estimates, which call for $333.7 million in sales and $0.42 per share in profit. The quarter closes at the end of the month, but a blowout is clearly in the pipeline. lulu loyalists are snapping up new digs, and I'm encouraged that comparable-store sales are reclaiming the 20% threshold. One of the few downsides recently was the prospect of comps trending lower from "spectacular" to just plain "great."

Other apparel retailers like Gap (NYSE: GPS) would downright kill for comps like that, instead of its gloomy negative 6% last quarter. Urban Outfitters (Nasdaq: URBN) similarly put up uninspiring comps of negative 7% last quarter. Both of those companies also operate high-end brands, like Banana Republic and Anthropologie, but shoppers of those specific names aren't even coming back like they used to.

On the margin side, wholesalers like Nike (NYSE: NKE) and Under Armour (NYSE: UA) also have lulu envy, whose 42.7% and 48.4% respective gross margins play second and third fiddles compared with lululemon's 55.8%.

If you're looking for a retail growth play to round out your portfolio, lululemon is the way to go.

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