Hi, our voipswitch system is running now, but not in high capacity. I can say that their Interface is quite User friendly and simple to use and their tech support is quite responsive, at least they repsonse to ur problem and try to fixed them up for u. So far we had try on tehir prepaid calling card, IVR/PIN and SMS callback..So far so good, but not yet tested under high traffic. There are little bug here and there , but will not affect much on normal operation.
Their Interface is not as fancy and impressive liek sysmaster, and their documentation is poor..buthow ever, we still feel very comfortable with it.