Shorter massage to save money is ok, As long as you don't cut back on your tip. Remember if you normally pay $80 for an hr massage and tip say $60 for extras, don't plan on booking a half hr and pay a $30 tip for the same extras. If you do I guarantee the level of service will eventually go down. The ladies want the same tips. If you book a half hr, then the room fee is reduced. That is where the money is saved.
Don't cheap out on the ladies gentlemen.