You've heard of companies beating analysts' expectations, but beating management's own "preliminary" revenue announcement? Now there's a neat trick! 

Such was the case with Illumina (NASDAQ:ILMN) last Thursday afternoon, as revenue came in $5 million higher than the preliminary announcement a few weeks ago. Apparently, the company decided to recognize revenue from a multiunit sale that didn't make the cut during the preliminary review.

Investors weren't buying it; shares dropped 3% on Friday. Some of the drop may have had to do with the stellar performance competitor Affymetrix (NASDAQ:AFFX) turned in a day prior; the one-time leader of the genomic chip market was up 29% on Thursday, after it actually turned in a profit -- something Affymetrix hadn't done in almost two years.

Investors may also be worried about the DNA-sequencer wars, which are hitting new highs. Not long after Illumina announced the release of its HiSeq 2000 sequencer, which can sequence a human genome for less than $10,000, Life Technologies (NASDAQ:LIFE) introduced its own sequencer, which can read the genetic information for $6,000.

Illumina may be behind in the lowest-cost-per-genome contest, but management didn't sound too worried about the competition on the earnings call. Part of the confidence may stem from Illumina's development of an instrument with a lower up-front cost, which can pursue other aspects of the sequencing market. Not every lab is focused on wanting the fastest machine for the lowest cost. Labs that aren't sequencing thousands of genomes a year will be more focused on keeping initial capital costs down, and Illumina's Genome Analyzer IIe should fit the bill, at less than half the cost of the HiSeq 2000.

I continue to think that Illumina and other laboratory supply companies like Waters (NYSE:WAT), Thermo Fisher Scientific (NYSE:TMO), and Millipore (NYSE:MIL) are a good choice for investors who may be a little skittish about investing in drug companies. At 35 times next year's expected earnings, Illumina is still priced as a high-growth company for sure, but investors don't have to worry about binary events like upcoming FDA decisions for drugmakers such as Dendreon (NASDAQ:DNDN) and XenoPort.

At least, as long as management's surprises aren't much more than $5 million.

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Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. The Fool owns shares of and has created a covered strangle position on Waters. The Fool has a disclosure policy.