Best Way to Call INDIA

[tipto]

HI Folks,

I am in process of comparing various options available for calling India.

Some of them are listed below. But not sure as to how exactly they all work any information would be useful.

1) Buy adapter like :
A. Use Skype AU 600 gateway , Very good quality if you use with SkypeIn number.
B. Use Linksys Sipura SPA 3000 or SPA 3102 gateways with or without Asterisk.

2) Use services from Vonage and other providers.

3) www.worldphone.in ( a legal service)

4) www.relianceindiacall.com

Parameters that I am looking for are:

No Long term obligation or contracts Pay and Use and bye bye.
Quality and latency of voice
Ability to call directly to fone without need of a PC
Ability to make unlimited call from USA (reverse not required)