With regards the manifold, I would consider putting a new lower engine mount on, you'll notice a grind/knock once it's fitted, it has less movement than the standard item, plus if your replacing it due to damaged flexi joints it most likely the mount that caused the problem. Brakes, I run Brembo hc with dc performance pads, good enough for road use. But as said the dc2500 are very good, the Michelin cup series run Brembo hc with dc2500 without any problems.
Are you running the manifold? I think the mount was about £100, so will see first if there is a problem. Debating whether to try and do brakes and tyres at the same time and chuck something really grippy on like an AD08