Okay in France maybe, but frowned upon elsewhere.
This word, along with the phrase "stovetop espresso" represent two peeves of mine. That strong-tasting short shot of coffee in a cafe? That's an Italian word, espresso(meaning "pressed"), and it's what you get by default if you order a coffee in Italy, Hungary and probably a few other countries where coffee is espresso. Nowhere can it be correctly referred to as expresso, save France alone, where the language often adapts foreign words and phrases to suit themselves; their use reflects the speed of an espresso. If you ask for an expresso elsewhere, you will likely get an espresso and a withering look. Most baristas are going to understand what you mean, serve you correctly and politely, and only a few will boorishly correct you on the origins of the word. But you have been warned. I've seen a few baristas get apoplectic over this mispronunciation. Beware the wrath of your barista.