[dba-VB] Low Cost Worldwide SMS providers

Hi All --

I'm looking for a low cost worldwide two-way SMS provider to be integrated
in my customer's application:

Google search:
http://www.google.ru/search?hl=ru&source=hp&q=low+cost+worldwide+SMS+provide
rs&aq=f&aqi=&aql=&oq=&gs_rfai= 


has returned the following links:

1. http://www.clickatell.com/products/two_way.php 
2. http://www.ficall.com/english/#/ficall/about 
3. http://www.animatele.com/index.html 


The first one - Clickatell - seems to be a good option. Do you have any
experience in working with Clickatell? Do you know and successfully used any
other low cost worldwide SMS providers in your applications?


Thank you.

-- Shamil