Can anyone recommend a good SMS Gateway device that sends and receives messages and has a reasonable API. We are looking for a hardware device that a Sim Card and works with Windows / .Net.

I am working with about 50 different countries (Right now 50 will only become more in the future) and dealing with that many SMS suppliers and their various methods for billing and sending / responding to messages is proving unmanageable. It may be much easier to have a single method and call it by country.

We do bulk send messages but from the logs this is at most 500 messages at a time (though it could be up-to about 1500 at a time) - mostly its small numbers far less than 500 messages.

Ideally would like to get message delivery data and error handling type messages back from the device. I am not interested in a hosted solution unless it has the ability to receive a message to a local number in EVERY country.