never use a 9" grinder then you'll take your f**king head off 
It was only yesterday my dad said he didn't want me using the 9" on a car. Bites enough on breeze blocks.
Never had an issue with a grinder before, had just cut a big chunk of dash bar out of a MK3, bites a bit but as you know, hold it correctly and cut gently and it's fine. Had a stupid moment and got the hump, held it the wrong way to get to something and kept my face out the way. Gently gently, wasn't gonna go right through but then it caught on something and jumped at me.
Don't think I acutally want to use the 9" after seeing how much this little thing can kick....