A PVP and a TA are apples and oranges, IMHO.
A PVP works for the cruiseline. A TA works for YOU. And as Donna pointed out, in addition to a good rate, a competent TA will also get those perks that a PVP can't offer.
I know that many people swear by a PVP and if that's working for you, then continue. But (again) as Donna said, a TA can help you book your next cruise on another cruiseline and can be a valued part of your future vacation experience for life!
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