Me personally, I would buy a 330d sport and then the change I would spend on a remap and bigger intercooler and a few other choice mods too make it your own. 530d and 535d are good cars but it's just they are a we'd bit heavy and if you want something that feels quite quick then the 3 series is the better buy. But it all depends on what you want out of the car at the end of the day