I understand from company sources, Virgin Australia (737NG) leave the AT armed when flying manually on final approach but de-select the speed function. I understand that this was the technique used by the former Ansett Airlines of Australia on their Classics before the airline folded over a decade ago. Pilots of AAA who joined the then start up airline Virgin Blue brought that technique with them regardless of Boeing recommended philosophy. Qantas NG AT philosophy started off leaving AT armed for manual flying then reverted to Boeing recommended procedures of AT off when manually flying unless in climb after take off.