I recently tried the Bigbasket.com. Their prices are bit higher than the supermakets. Considering they save on shop rent, employees cost, electricity bill etc, their prices should be 10-20 % cheaper than your average supermakets. I did a comparison item to item and big basket turned out to be decently expensive.
Also, you always dont get 1 kg when you pay for 1 kg.
The fruits and vegetables also dont taste the same. I guess they are treated with chemicals to help them store longer.
Thanks,
Nirav.