I had a private line agent in past years, but opted out of the program. I couldn't find even one advantage to having a PL agent.
1. With a PL agent you can only do business when that agent is on the clock. This means 16 hours a day when you CANNOT do transactions, and several days a week (e.g. weekends) when you're similarly shut out.
2. You still had to go through the same authentication scheme with the PL agent as with the regular Diamond line.
Are there any real advantages to a PL agent, other than feeling "important" because you have something that most people lack? (Even when that "special something" is practically useless?)