They are just the same as Vivaros and Renault Traffics but I had an 03 Vivaro and had nothing but trouble with it,gearbox went and alot of other stuff,smart looking vans but it cost me a fortune,always in the garage etc.
I believe Vivaros,Traffic and Primstar are all the same van but with a different badge,your better off getting a newer model say from 06 upwards.