Manchester easily the best uk race track, so many lines, always deliver great racing. Cardiff ( people say close racing) well as it's the size of a large roundabout it would be!! Huge advantage off gate 1, check the stats. Day trippers may live cardiff, speedway fans would prefer manchester, and the great GP at coventry. If people like "comfort" of a seat, you welcome to it, for people who like to stand have a different viewpoint. If you like hype, loud music enjoy cardiff, if you like the actual product, I'd say manchester every day of the week.