To add to this warrranty thing.
Page 10 on the manual talks about:
The intend use for the tool."The hand operated circular saw TS55 is designed exclusively for sawing of wood and wood-like materials and plastics."
Page 18 is selling you on a Dust Accesory for cutting plaster and cement bonded fiber boards.
"Due to a high build of dust, using a cover (accessories) That is mounted on the side of the protective saw is recommended."
Sounds like their talking out of both sides of their mouth

Somebody pointed that out in a thread I posted a while back about using a TS75 to cut soundproofing drywall that had a layer of cement board in it. They definitely need to specify whether cement board is included in their definition of "wood-like" materials, or, more importantly, whether cutting it with the saw specifically voids the warranty.
Does anyone have this accessory? How well does it work?