@rbkumaran I said that
They value their postpaid customers most. But that doesn't mean, you should believe them blindly, keep an eye on Bills (and specially the details). As for me, I never had any issue. One more thing, is that Vodafone charges some amount for detailed bill if sent by post, but if checked and downloaded from MyVodafone it's free for all. If you don't need bill by post opt for Green Bill (aka no bill by post, only email). In email they will anyway provide you detailed bill without any charge.
The last but not the least, don't pay any security deposit. It was norm when postpaid concept was started. But nowadays, security deposit is not at all needed. I have got postpaid for my dad and my gf too, never paid security deposit.
I know stores (be it Airtel or Vodafone) asks for it, but this is no longer mandatory. Just say them, "in my office they are giving me CUG plans for free without any security deposit, why should I pay you extra, I'll get from him." That will take care of the security deposit.
And yeah, if you know someone working in Companies where they offer CUG plans, then ask him/her to get the postpaid connection for you. CUG plans have many benefits and perks. Like call rate are very low (like as mine is 10p/min local, 30p/min national), and you get some free sms and data every month also with generally a Rs. 100 /- bill discount. This may vary from plan to plan, but some perks are always there.