Only speaking for my 2021 MiA Mod Shop P Delivered to dealership with full inspection tags. Nut cut so low multiple strings were benched/witnessed on the first fret instead of the nut meaning it wasn't possible to tune or intonate. No shielding. Several frets so high you could see the tang. Bridge ground wire not pulled through the routed hole, not connected to bridge.
That said, a PLEK cut bone nut and a PLEK job on the frets and 15 minutes in the cavity and it's one of the best playing and sounding basses I've ever owned. So I'd do it again. 100%.
So we're clear, I love Fenders and I want MiA more so it's worth it to me.
My MiM Tele neck that I got from Fender direct (parts page) is as close to perfect as any new neck I've bought. Well done.
Here's the thing, the CNC tools don't know where they are installed. People have good days and bad days.
Do you know if the master built is shielded?