For rebirth using 5w30 and 10w40 both is ok for the car.
However, it is better to use 5w30 fully synthetic, as it will give better fuel efficiency.
You can stick to 5w30 as long as you are not getting any oil burning while using 5w30. If when using 5w30 there is oil burning then only you should use 10w40.
For 5w30 Fully synthetic you can use PSO 5w30 or Shell HX7 Plus 5w30 or even Honda 5w30, all 3 of these oils are API SP. No need to go for Mobil1 as its higher priced and wont give significant benefit over the above mentioned oils which are all API SP rated.