Picked it up. Total cost £300 so not too bad (Over £900 with out warranty + Mot cost) .
But I have just check the video they sent me and they mention a leak that maybe coming from the head gasket, so that's good. Didn't get told that when I picked it up as I would have left it with them. Looks like I might have ETA doing more work on it then I thought now.....
Have asked BMW to ring me back tomorrow so I can find out more about it.
Edit: Spoken to BMW today. Basically I don't need to worry about it and it will be checked next service. If its still there or worse then it will go under warranty. So I have just cancelled ETA as I cant go having 3rd party work and parts put on it until then. At least the warranty will cover me if my engine does decide to nom its self to bits.
So my plan now is to book it in for a oil change in a couple of months and get them to check it then and go from there. Hopefully have it all sorted, what ever it is by the summer.
I hate cars.