Hi I am planning to use a T1 card w/ Freeswitch and intend to use CAS (Robbed bit). Can someone please guide me as to what the best card/vendor would be. From what I can see three vendors support FS:

 

Pika

Sangoma

Digium

 

Any suggestion would be appreciated. I intend to use 4 or 8 T1 on a single card.

 

Thanks in advance