I am already using chan_dongle for both inbound/outbound voice and Longcode as SMS. I have solid 7 years experience inn asterisk. I have done may IVR, Speech IVR, Conference Bridge application around Asterisk. I can show you live demo of chan_dongle any time.
we done installation and configuration of chan_dongle over asterisk 13 , 12 , 11 , and also freepbx , a2billing if you want without additional fees
thanks