He will probably act on quicker ground on the flat as he is not jumping so there is less strain with him not landing on the ground after jumping – he has a very fluent action and i would think that only good to firm ground would be a no no with him.
The last three runnings of the John Porter have been on good (last year), good to soft (when notable soft ground performer Hamish won it in 2024) and soft in 2023. Two of the last three runnings were won by horses officially rated 100 & 103 so I think he could be capable of winning a G3 if he faces rivals at those levels. Obviously if a horse like Hamish (117) turns up then that is an entire different proposition.
Turf and a stronger gallop will suit him much better but what will be really interesting to see is exactly what he does when he comes off the bridle and under pressure and he has to battle.