I've been using Tata Indicom's data card based internet services for the past 2 years or so. and my experience about the internet service quality has been above satisfaction so far. After filling up the application form, and paying 4990 INR upfront for the data card, i got the card delivered at home in 2 days. Pretty fast indeed.
Data card connectivity speed: The Huawei EC321 CDMA card is rated for about 156Kbps. Initially at the place where i used to live, i used to get about 140 Kbps speed without fiddling too much with the antenna and direction. At my current residence too, i manage about the same speeds, which is more than enough for my email and IRC applications
Setup and installation: The data card comes as a PCMCIA device which can be plugged onto the PCMCIA slot of your laptop. Its probably straightforward to install it in Windows. There's a desktop manager application included in the installation CD with puts a dialer-cum-sms inbox checking app shortcut on the desktop. Getting the internet working on linux is even easier. Check
how to get the data card running with wvdial here.
Tariff plans: The data card costed me around 4990 INR some 2 years back. It should be cheaper now. The USB pen drive shaped Plug2Surf ones are definitely cheaper. I am under 1GB plan which costs me less than 800 INR per month with taxes included, as i never cross my 1GB limit.
Network coverage and roaming: Its based on Tata Indicom's CDMA network, so internet services work wherever there's tata indicom's mobile phone network. So far, it has worked for me in all the cities i've traveled in india. There are no charges on national roaming if you are using the data card only for internet services.
Verdict?: Its a good gadget to keep along if you are traveling. Internet works just out of the box, without having to ask anyone for network access or proxy authentications. I haven't used data card services from Reliance or Airtel, but i dont really have a reason to switch services as yet. Lately there have been days when the internet is pathetically slow but then it comes back again.
Where to buy?: You can visit their website
ichoose.in and place an order. If you are in Mumbai then let me know, i can pass over the contact information of their sales representative and he'll take care of the rest. My email address is anurag (@) gnuer.org