Hello Paul,
Reading your text I think you have 18inch rims. But to your question....both brake set ups are very good. A lot of people who choose for the AP brakes are choosing also for the name. A bloke I know with a 400bhp sapphire with monster 4pot Hi-spec 330mm brakes said they are very good. So Hi-spec 355mm and 6pot will do a lot better. And they are the same price as the AP 4pot 330mm. Which also are very goode. So it's up to you.
Best regards,