Both transliterations are fine and natural. You can choose whichever you like unless you are a professional writer and have to follow some opinionated guideline. But I feel I see the elongated version more often in daily life.
When you transliterate Western foreign names, short names usually have a trailing `` (e.g., , , ). If the name is three morae) long or more without the trailing ``, then the trailing `` is often optional (e.g., /).
See:
* or ? Words borrowed from English which end with -er