[Chris da PPV Hunter]

What do you prefer guys ?
Which one is the best?

[Ripanno]

I have heard good references about using Twilio for that.
Due to their big userbase, specially if you want to send SMS to multiple countries, they have solved a lot of the country-specific oddities so it causes less headaches at the end of the day.

[nilboy]

Twilio is good but expensive. I like Nexmo or Plivo. Twilio is also shit outside the US in many countries as far as deliverability.