That mongrel usage must add color to your writing, though. In the digital age Americans have been picking up more British expressions. It can be an affectation--and come across as pretentious--but the Brits have some expressions that are more precise or vivid than their American-English counterparts (e.g., "gobsmacked" for "thunderstruck"). So I understand the temptation to engage in across-the-Pond literary shoplifting :).