I'm sorry you had a bad experience with version 7.x.x.x. However, may we have a look at Host logs that didn't come online? Did you manage to ugrade the hosts to version 7.x.x.x? Or were you connecting to v 6.x.x.x. hosts?
Actually they do respond :) Only they never answer the question why. Instead, they answer that "Administrators can create a detection exclusion from the ESET PROTECT console centrally for all clients."
I'm not in a position to discuss the merits of different corporate antivirus software. But..
According to VirusTotal there are no detections from Kaspersky, TrendMicro, Norton, Symantec. All detections come from several junk and half-baked a/v engines ...and ESET. Well, that's a good company for an a/v vendor that claims to be in the top-10 (sarcasm).
Your key upgrade may either be free or paid with a 50% discount. Please, read our Upgrade Policy, the section "Upgrading product version". We have never changed this policy for customers who purchased and use version 6.x.x.x license.
If you are not willing to upgrade to v. 7.x.x.x you can use version 6.x.x.x along with your v. 6.x.x.x license key forever. To roll back to version 188.8.131.52 (the last v.6 minor release) please visit this v.6 download page