When I write Japanese in the charset Latin I (ISO-8859-1), I often use �, �, �, �, � to indicate that they have a long vowel, so I would write as Hikōen and Bōen. But in the charset JIS (ISO-2022-JP), I do not apply them because those letters must be garbled, so I would write as Hikousen and Bouken. Personally I do not like Hikosen or Boken.