As a matter of fact McLaren also call their orange "Volcano Orange" As you would expect it is much deeper, and richer than the MGF Volcano. They must budget a bit more per car for paint.
One interesting fact I found out recently is that you can only buy McLaren paint direct from them. They don't make their paint codes available.
Here is a picture of the first McLaren I ever saw (in Volcano Orange), at an event in Seattle Washington in 2012. Now they are quite common where I live, certainly more common than Modern MGs!
Here is one at our local Cars and Coffee event. Note the New Driver placard.
Kind of spoils the appeal for me.
Even worse, here's the front view.
One last gratuitous orange car picture. This time there's a whole grove of them!