You don't need to press to start and stop the timer... When you go to the lap timer on the MFD press the down arrow then it goes to 'since start'

press ok button, then it'll say 'start measuring time when driving off' and it'll start as soon as you boot it.

As for my tyres, yeah I'm very impressed with them, glad mine didn't come fitted with bridgestones.
1st gear is a pain in the arse to get any traction from. If they didn't spin up so much it'd shave another few 10ths of the 0-60 time I reckon