You will need a remap if you remove the second cat.
In the centre section it is a resonator (silencer) not a cat.

+1 for milltek

I've got a 2.75 miltek turbo back system for mine with a balanced header and tbh it's pretty quiet (I used to have a civic type r with a spoon exhaust and that was too loud tbh).

Sorry to thread hijack but does anyone know where I can get a decat for mine? No need to worry about MOTs as I know some friendly MOT testers ;)