Which is better-prepaid or postpaid voice plan? Analysis for India

The benefits of working for a telecom company is that you get some insight into how the market works. While I do not claim that a month's experience has made me a guru on this(despite what my friends may think!), some useful insights are below. As always, I take resort to the classic MBA answer 'it depends', to point that for each person depending on their circumstances, the conclusion would differ. For data, there is a separate blogpost.

1. Tariffs:-Since prepaid customers(other things remaining equal) are seen as more likely to churn, telecom companies offer them good tariffs, and newcomers try to lure them with great tariff plans. While companies DO reward their loyal postpaid customers, the latter are likely to take postpaid for reasons like company reimbursements, address proof, loyalty and not tariffs, so prepaid seems the winner in this. Prepaid 1-Postpaid 0
2. Customer Service/Billing :-Companies need to retain data for their prepaid customers for a much lesser period than for postpaid customers(due to TRAI billing norms). Hence, CRM analytics, customer segmentation etc becomes easier for postpaid than prepaid. This is not to say that high prepaid spenders don't get differentiated customer service, it is just that companies might not go out of the way to resolve issues for their prepaid base whom they see likely to churn out. And given that getting an itemized bill will cost around Rs 50(ceiling imposed by TRAI), disputing charges or getting waivers becomes much more difficult for prepaid. Also the small fact that in prepaid, your money is at their disposal but in postpaid, your not paying is their bad debt. So once money changes hands, it is more difficult to get it waived or so. Prepaid 0 Postpaid 1
3. Flexibility:-This is really where prepaid scores over postpaid. For example, if you suddenly need to send bulk SMS or make ISD calls in the middle of your billing period, you need to wait for sometime before switching to a better plan, if you are a postpaid customer. But if you are a prepaid customer, just take a top-up/Recharge voucher and you can immediately change your usage pattern. For example, I've made calls to Singapore and USA for hours this month, at a rate of Rs 7.4/minute, but for a Rs 14ISD prepaid voucher, the same calls would have cost me Rs 2.99 only. Ditto for sudden data usage needs etc. Prepaid 1 Postpaid 0
4. Usage based recomendation of best plan:-Though Airtel launched a portal earlier this year giving such recomendations for prepaid users as well, that is not yet an industry practice. As the telecom companies have data usage of their postpaid customers, they can more easily crunch numbers and offer them better plans. Ideal for those customers not savvy enough to hunt better plans from the same telco. Prepaid 0 Postpaid 1
5. Address proofs:-Here, there is no doubt that postpaid is easier. Though one would have utility bills etc, a telecom bill is the easiest address proof to generate in 3months,especially for migrants. Prepaid 0 Postpaid 1

These were the points which I felt crucial to decide between the two. Would welcome your comments.