For that price, I agree, get them assembled and tested and be done with it.
If they have to shim them they will take the tip off anyway. I built my Jammer 4's myself and then had them pop tested and got them within a few bar of each other after 4 of the 6 were re-shimmed.
Does City Diesel tell you what they pop tested at? That is the only advantage to having it done by a shop you know. They told me exactly what each injector pop tested at and I knew they were within few bar. Maybe City Diesel gets them even closer.
I am thinking of going back to jammers (stage 5 this time)
Jason