Hi Claudio,
Nice to hear from you. I have no experiences with other IVR programs but I do find IVM powerful for my needs. I am able to easily integrate with databases and create complex ogms. However I have the feeling that there are other solutions out there much more powerful and maybe much more cheaper thanks to the open source community. I wonder if you have played before with Asterisx or Trixbox (very popular) or other commercial sofware similar to IVM.
Another thing I find useful is the SIP lines but I am not able to make them work. They answer the call but do not respond to the DTMF. Are you familiar with that?
One good point for IVM is the fast learning curve and easy configuration. Yes buggy but has a lot of documentation and at some point but I see it as the windows of the IVRs that productivity (on the short term) is there. Other systems require more time to learn and master however, once you know, solutions are robusts, scalable and powerful.
laca.-