Yes. To avoid confusion when checking-in and when boarding, always refer to "Transit without visa" and not "Visa on arrival" (which is something totally different and much more difficult to arrange). "Transit without visa" is the term used in Timatic, which agents might look at to check your eligibility to board.

72hrs TWOV has taken more than 30 minutes to process on each of the three occasions I've used it at XMN, but 24hrs should be quicker. Just present printed confirmation of your onward flight (I usually highlight the destination, date, time, ticket number etc) and a completed landing card.