I have quite a few experiences on their service
1) Timely delivery:
They have options to deliver within a day for 100 Rs. I would say its worth it. It saves your time, energy and petrol/diesel as well. When they say 24 hours it will be delivered before 18 hours. Cashless deliveries will also be done before the time they mention on the site.
2)Courier service:
Since amazon has their own courier service. There is less confusion and they have card payment option as well and the courier guys prefer that as well. That means even a penny need not be given to courier people for not having change.
3)Product quality and rating
You can trust the ratings given in amazon and buy it.
4)Return policy:
believe me, returning in amazon as easy as buying. Their person will come and collect it to and your money will be credited back
Trust me amazon is the best!