Aviator, when is your yearly service due. If it's not too far away your Delvac 1 will go waste. Go for Delvac 1 if you have a good amount of time and KM interval till your next service. The Delvac1 R-O-I is only when you extract everything from it. Also, double check Maruti packaging of Delvac 1. Can be Delvac MX 15-40.