I've just done my grade 8 piano, and it went really well (Whether the examiner agrees is a different story!).
I started with scales, and I think I responded quickly to all of them, and there were no mistakes in any of them except one where I did the Harmonic instead of Melodic and she let me do it again. All the arpeggios etc went fine, as did the scales in 3rds and 6th's (even C# minor in 6th's which I was dreading, but played it with no mistakes at all for once!).
My pieces were good, particularly the Beethoven. The Cimarosa from the A list went a lot better than expected, and the mistakes that I was making the day before strangely didn't happen in the exam (Although I did repeat a bar for some strange reason!). The Beethoven on the B list was really good, there were a few slips here and there, but that's to be expected. The Gershwin on the C list was good, although I mucked up a bar or two that could of been better, but oh well!
Aural was interesting! The singing the 3rd line of a piece started ok, but I forgot the ending! The sight singing also started well, but the ending "lost it's way" (what an old examiner wrote!). The other two tests went really well though, except I forgot the name of the modulation when it changers key (eg. F major to G minor).
Sight reading was also very good. A slip or two, but oh well!
Overall I think it went really well, but now i've said that, I'll end up failing or getting 101!
Now I have a long wait for results! (well, hopefully not that long a wait!)
Jacob.