There is a rather detailed report of the week I spent at the Perugini & Visini workshops in 2003 published in my book Double Guns and Custom Gunsmithing.

Where you came up with the notion of any P&V and Purdey connection is a mystery to me. I surely wasn't the case in 2003 nor have I hear about it since.
My best advice about any Italian (or imported) gun is to find out about service in this country. As for comparisons, all I have is personal preference I don't imagine to be all that important.
Best,
Steve