Are you supposed to mitre the internal corners of metro or should you scribe?

[D hug]

The champers would obviously create to big a grout joint.
I'm thinking a mitre. Scribing might be a bit wobbly looking?

 

[Blunt Tool]

Install your first wall cuts as normal then when you do the next wall cuts mark the tile and cut at the longest point ie just before it turns over the edge of tile. Then take a tile file and file off some material from the thickest part so that it shapes to a good finish. Colour match silicone down internal corner to finish

 

[acaciaguy]

Personal I mitre them. But either way that gets a nice finish is fine