Well im not sure, If they are both in standard trim then the 400 may have the edge!! Also depends where the track/road is, cadwell i think the 250 would have it, donnington and the 400 will have the space to get around quicker!!! on paper the 250 should be quicker as it has similar power to a standard 400 but is alot lighter!!!

of course this is my view as ive riddien both an NC30 and a 250 in standard trim! other comments to follow im sure...