We had a terrible experience with Knowledgevision sales rep Zack Potter not too long ago. This guy was unhinged!
We were not really happy with the software we bought (really not much value for the thousands we paid) so we did not want to renew our service. So Zack Potter (think of Harry Potter, only a really obsessed and evil Harry Potter) kept contacting us saying he was my "customer advocate". I kept telling him that we did not want to renew our services. And the more we said no, this Zack Potter just went bonkers on us!
He started and continued this nonstop email chain to us which was downright spooky -- when he did not get the "yes" he wanted from us, he started sending us sarcastic, demeaning and personal attack emails.
After a while, we told him flat out that we never experienced such an insane response from a sales rep ever in our lives or company history, which resulted in even more vicious and angry emails from him.
So, if you are thinking of using Knowledgevision, we should caution you to think twice about it (unless you are willing to bear the wrath of Zack Potter).