I can not say which one is better because I have never used Shell oils. I use Caltex's Havoline Motor Oil, it comes in a One litre, black plastic bottle, the oil is reddish in colour. It's grading is :
Make sure you get the original, large Caltex filling stations are a better place to get the oil.
If you choose Shell, then get it from a large Shell filling station.
After the first tuning, stick with the same oil. If you decide to change the oil brand or type have both the old oil and the oil filter replaced. Never mix a different type/brand of oil to refill existing oil. Never use the open oil available at filling stations, it is not meant for engines that rev up to 10,000rpm (like motorcycles).
You can use any lubricant from SAE 10W-40 to SAE 20W-50. API rating must be SF or SG (for all motorcycles). NEVER use Havoline Formula or any other oil with API ratings of SL or any other, which are for Cars (dry clutch).