Living in Queensland, Australia, sunscreen is a necessity if you don't want to end up with skin cancers. I use it on every ride. Even if your ride is from 5-7am, sunscreen should at least go on the face and arms (if you are wearing a s/sleeve jersey)- it will also protect against damage from the wind as well as the sun. If sunscreen dripping into your eyes is a problem - the people at Ella Bache reckon theirs is 30+spf, non-greasy, doesn't drip and doesn't sting the eyes. You pay a bit more for it though.