QTelNet is a sub company of QSound Labs (
www.qsound.com) who has been in the sound industry for 20 years.
As a reseller I can testify to the quality and easy of setup. The only way you are going to know who they are and the reliabilty is to try some out for yourself, that is what I did after I heard good things. They dont seem to be out there to compete with Cisco or Nortel but to fit in the medium sized solution where there is no need to forklift to add VoIP. Hope this helps.