PCW exhaust mod & UK BMW warranty

[757_flyer]

Hello all

Apologies firstly if this has been discussed before. I have tried searching.

Im thinking about getting the PCW mod for my F80 by Paul from PCW mods in Bedford. Im in the process of finding out about how the physical changes could affect BMW UK warranty. Has anybody on the forum had the mod whilst under warranty?

Also has anybody tried any intermediate modifications such as just changing the rear box internals which will avoid having to cut the exhaust pipe in serval locations thus avoiding visible modification?

Many thanks