Sorry to do this but this is from an email I received.
from Mondo Pacific (Joe Hoekstra) on spikes attached. Stick to a maximum of 7mm for all events, either pyramid or Christmas Tree and you’ll minimize damage to track, but still cover all events needs. It is essential that all start-block spikes be checked at 12mm only. Shorter will slip, longer will dig into bitumen under the 13mm Mondo. Best to specify that only stadium-supplied start blocks are allowed on the track – at all times, irrespective. Needle spikes are a big no-no – a disadvantage to the athletes as they are grabbed by the Mondo’s composition and under honey-comb (and also by Rekortan, Spurtan etc.) and will also go right through to the bitumen underlay on the thinner poured tracks.