I would say never buy mobiles online and avoid shipping by any Indian courier company including Indian post. This is because there would be 75% chance of steal or misplace in transit. When it comes to cellphones try to have hand to hand deal.
i have used blue dart they r the safest and they check the cellphone and take. they charge rs 230 or rs 350 max depends on weight but they r best. most of the ebay dealers also ship there mobiles from blue dart only.
My opinion is to go for DTDC Blue. It's quite safe. They accept the mobile phones and will cost you about Rs. 200 per shipment or you can go for the Indian Speed Post which will cost you as per the weight (in kilograms..)