They are very quick to respond when there's an issue with our system! I can't think about anything that would be bad at this point because everything has been great so far!! Very helpful staff who know their stuff in all aspects concerning business communications within your organization. The only thing they need more training for it seems like some people have trouble understanding what we're trying tell them sometimes (weird language). We've had nothing but problems since switching over from another phone service years ago; however, coher was able to resolve every one quickly without any issues or complaints whatsoever - even after months!