The phrase "a main selling point" is correct and usable in written English.
It can be used when discussing the key features or advantages of a product or service that make it attractive to potential customers.
Example: "The smartphone's long battery life is a main selling point that appeals to busy professionals."
Alternatives: "a key selling feature" or "a primary selling advantage".
A main selling point for Chinese smartphones has been price.
So what do you do when your product loses a main selling point?
But a main selling point of the new A320 was its fuel-efficient engines.
But nobody has previously made direct online access to analysts a main selling point.
The industry is also moving toward battery-powered vehicles, a long-term trend that could blunt a main selling point of conventional sports cars: their speed.
That's a main selling point for the Big Gulp, the much-loved drink sold at 7-Elevens across the country: bigger is always better.
A coin's main selling point is a 30-year life span versus the paper dollar's 14-month span.
A team of grown-ups creates a musical whose main selling point is teen sex (the first Broadway posters showed the male lead mounting the female lead) and whose female teen characters, shortly after wailing to their largely grown-up audience that they are bad-girl love-junkies, come forward to sing of how terribly, unfairly painful it is to possess a teen sexuality that fascinates grown-ups.
For a candidate whose main selling point was supposed to be his electability, these are terrible numbers.
But in tech, where many companies don't make profits under traditional accounting measures, the promise of ever-growing popularity is a company's main selling point to investors and employees.
Under pressure to pay its own way and rely less on handouts from Moscow, the company is now pushing to develop Barentsburg as a tourist destination, a hard go as its main selling point, aside from a stunning setting on a mountain-fringed fjord, is its authentic Soviet griminess.
