Zultys vs Aircall

My BIGGEST complaint is the complete lack of user reference material. Zultys has a small 4 page "Quick Reference" guide that basically gets you making phone calls and not much more. Our previous phone system had an excellent user guide that detailed every feature of that phone system. The only training we got was what we found on YouTube! I will say the audio quality is excellent. Navigation is buried and confusing. Again, wouldn't it be nice to have a detailed user guide! Another negative is their handsets. While they are sleek and pretty, they are slim, hard to hold and fragile. I purchased phone pads to compensate for this as my guys were complaining they were impossible to hold with their cheek and shoulders while talking on the phone and working on the PC. I suppose a work around for this would be headsets for everybody. This system is also prone to just dropping calls. Our fax machine still drops calls before the system transfers to hold before the fax machine picks up. Nobody seems to know how to fix this either. Needless to say we miss our old system.