The best thing I like about convergents is that they are very reliable which makes me feel comfortable in using their service as my communication platform with clients all around world! There was nothing really bad to say but if you want something more secure than other providers then this might not be your choice of provider because it lacks security features compared others such us Aastra or Avaya etc..
If there's anything i dislike its only price though considering what we get from them; customer support (reliable), quality products/features & pricing can't beat those things so far at least where im currently working now!! Communication between various offices across different countries has never been better since implementing voice over internet protocol system here by converting our current phone lines into VOip systems through convergence telecoms solutions. No problems yet except maybe some minor issues when having conference calls especially during peak hours however everything worked out fine after contacting technical department who helped.