Well, I'm sceptical. If you're making an artist signature pickup, why make the production version significantly different from the version the artist uses? Unless they actually use different materials - for cost reasons, as I said - it's no more difficult to make a "good" pickup than a "bad" one.
I appreciate that a "custom shop" version will have a greater degree of care and attention - perhaps they tweak each individual pickup to the particular guitar it's being fitted to. But that doesn't make it necessarily "better" than a mass-produced pickup. Once a custom shop pickup's been designed, there's no reason you can't consistently reproduce it - or at least get very close to it - on an efficient modern production line.
I just smell internet BS. Much like the "Older BKPs are Much Better" thread the other day on this forum.
Sorry, way off-topic.