In the market for one of those new HDTVs with the beautiful picture and the big screen? Be careful who you ask about it when you're buying one. Or so suggests a new survey out of the U.S., which claims to show that some electronic store salespeople seem to be steering customers to one kind of set over another.

And it may not come as a surprise to hear the main conclusion - the one they "recommend" just happens to be the more expensive model.

While there are several different kinds of HDTVs on the market, the two main contenders are LCD (or liquid crystal display) and plasma. In general, the LCD sets tend to be more expensive. So when consumer research company J.D. Power and Associates sent mystery shoppers into various stores to see which sets were recommended by salespeople, they were startled to learn that most 'customers' were told they should buy an LCD model over a plasma - regardless of the buyer's needs.

Three out of four stores tested showed the same result. And it wasn't just the recommendation of what's generally a more expensive set that was troubling. A good 37 per cent also stated as "fact" that plasmas are prone to 'burn in' if an image is left on the screen too long - a complaint that's no longer valid.

"Although burn-in was once a problem with the first plasmas to hit the market, this has not been a serious issue for several years," advises J.D. Power's Larry Wu.

And ironically, many of the sales reps also failed to state a few of the actual advantages of the LCDs themselves, including the fact they're lighter, they consume less power than the plasma and that the latter make can often reflect distracting room light depending on the geography of your home. Less than a quarter of the vendors bothered to mention any of the facts.

The survey was conducted over a six month period and used more than 2,000 secret shoppers who asked about sets of 40 inches or larger. "At most retail stores, large-screen television shoppers face an array of flat panel sets that all look essentially the same to the untrained eye," Wu explains. "Which is why recommendations from salespersons carry so much importance."

So what should you do if you're out shopping for a set? Do your research before you go. There's no shortage of unbiased information of the differences between the two on the Internet. Find a reputable site (such as the ones listed below) and make your decision based on the known facts.

Also, try to go to a store where the sales staff aren't on commission. They may be less likely to try and convince you that more expensive always translates into better value for your money.

And seek out stores that specialize in electronics. The survey found that larger department stores that sell everything tend to have salespeople with a more limited knowledge of HDTVs - and thus may not be able to answer your questions with as much detail.

But what about price?

"Television shoppers who visit mass merchants may be more concerned with obtaining a low price and may not be seeking expert advice," Wu notes in a statement. "However, television shoppers should be aware that the lower prices they find at mass merchants are primarily due to the fact that these stores tend to carry second-tier brand TVs, rather than major brands such as Sony or Panasonic. When pricing for a specific television model is compared at each type of retailer, the prices are surprisingly similar.  In addition, many specialty retailers and big-box stores provide price match guarantees."

LCD vs. Plasma Chart

Consumer Reports: Why buy a plasma TV?

Consumer Reports: Why buy an LCD?

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