Note that if there is a lot of text traffic on a given number, carriers like AT&T, Verizon, et al will block texts to and from that number until the traffic subsides. What's worse is that if you send a message to that number from the Twilio dashboard, its status will be "sent," but you will not actually receive it. Apparently in the world of SMS, "sent" simply means the message has been delivered to the destination carrier, and it is not a delivery receipt like with iMessage or BBM.
Twilio suggests that, to reduce this risk, you load balance across a collection of such numbers, or purchase a short code, which isn't cheap: http://www.twilio.com/sms/shortcodes
Note that if there is a lot of text traffic on a given number, carriers like AT&T, Verizon, et al will block texts to and from that number until the traffic subsides. What's worse is that if you send a message to that number from the Twilio dashboard, its status will be "sent," but you will not actually receive it. Apparently in the world of SMS, "sent" simply means the message has been delivered to the destination carrier, and it is not a delivery receipt like with iMessage or BBM.
Twilio suggests that, to reduce this risk, you load balance across a collection of such numbers, or purchase a short code, which isn't cheap: http://www.twilio.com/sms/shortcodes