I think one of the big challenges here is the ramp and sometimes there is turnover you don't expect. I have worked in other inside sales jobs and turnover is a fact of life. You can almost pick who will make it and who won't based on attitude and activity.
I have read some of the comments here and I am guessing they are people who left unhappy. I think that can be seen as a con of working here. People leave here and then write terrible comments online. Sometimes it can be discouraging,but what helps me is I talk to the people on the phone who I am working with or calling as prospects, it lightens the day. If you think positive and work on hitting a goal, you usually end the day on a good note.