Yup, it is. I did a few laps with the Lambo to record the below but last time we used the N800 class I found the Aston Martin Vulcan faster. So I'll be giving the a go even though it's such a pig to drive.
I was quite surprised by AC, the SLS handles quite differently in AC than GT. I've had some massive oversteer moments in AC but find the GT Sport version quite stable. In AC, the track is slightly different too, it's more slippery running wide between T2 and T3 and it's horrible trying to hop the kerbs at the chicane at the end of the lap.
Reference laps for y'all too. As for round 1, these are done after 5-10 laps so I know there's room for improvement but should work well as a guide.
GT Sport (1:34.582) - Part of a clean lap round here to really cut the chicane at turns 2, 3 & 4 - even in sport mode you can hook one wheel inside the sausage kerbs and get away with it. Plenty of time is also gained getting a good run out of t4, the chican and the final corner - though on this lap I went a bit too deep in to T13 and T14.
AC (2:01.114) - Similar to above, you can get a decent chunk of time if you get out of the hairpin at the bottom of the hill (T8), T12 and the final corner. Most of the rest of the track is just about keeping your minimum corner speeds up.