It was another bon voyage for Steiner Leisure (NASDAQ:STNR) shareholders. The provider of spa services on leading cruise ships and many resort hotels turned in another market-clobbering quarter, though it wasn't exactly smooth sailing.

Yes, the company posted earnings of $0.75 a share. That blew past the $0.61 per share that Steiner had earned from continuing operations a year earlier and the $0.64 a share mark that Wall Street had been expecting, but it was a lot closer than that. There was a $1.8 million income tax benefit during the quarter. Absent that, earnings would have clocked in about a dime lower. That still finds Steiner beating estimates -- something it has done in 18 of the past 19 quarters -- but let's approach this report a little more critically.

Despite recent announcements of deals to run hotel spas in places like Cozumel, Dubai, and Palm Beach, Steiner's bread and butter business remains running the floating spa operations on cruise ships owned by companies like Carnival (NYSE:CCL), NCL, Disney (NYSE:DIS), and Royal Caribbean (NYSE:RCL).

In that sense, the one number that concerns me is that the daily revenue per staff member dipped during the quarter. It wasn't by much --- down from $450 to $443 -- but it's the first time that I recall seeing that number clock in lower than the year before. This is a seasonally sleepy period. Revenue per staff still came in higher for all of 2006 than it did in 2005. I would keep watching that, though.

There was one more rough current in last night's report. Revenue shot up 20.7% higher -- and that's good -- but operating profits rose by just 5.7%. In other words, operating margins contracted during the period. It was a challenging period for some of the cruise lines, so one shouldn't expect perfection out of Steiner. To be safe, I would still keep an eye on how operating margins and daily revenue per staff figures stack up over the next few quarters.

With 126 cruise ships and 55 land-based spas, Steiner continues to grow its reach. Cruise operators keep adding bigger ships to their fleets, and Steiner is there to collect the extra passengers without having to pay the shipyard or deal with the fluctuating fares. Those welcome traits have made Steiner a solid recommendation in the Rule Breakers newsletter service. The shares have gone on to double since being singled out in the fall of 2004.

Just keep an eye on those waves. Steiner may seem like a bargain, at just 17 times trailing earnings -- and it is, really -- but one should always know where the lifeboats are.

If you want to read Rick's original buy report for Steiner and all of the updates along the way, take advantage of a 30-day guest pass to the Motley Fool Rule Breakers service. Disney is a Stock Advisor selection.

Longtime Fool contributor Rick Munarriz will never be confused with a metrosexual -- his socks don't even match at the moment -- but he has taken in a pair of Steiner spa treatments on the Disney Magic. He does not own shares in any of the companies in this story, save for Disney. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. The Fool has a disclosure policy.