I just installed my coilovers on my GTR. I had never done coilovers before but it was pretty easy. Literally 3 bolts on each coilovers. Just needed to remove the back seat and parcel shelf to gain access to rears. Oh btw if you are doing this at home then on the front you need to jack up both sides to the same height to release tension to get the coilovers to slot into the mounting points.
I went with MCA race primes with 14kg front and 8kg rear springs which is between their default Tarmac and circuit set ups.
I thought they would be boneshakers on the road but they ride the bumps pretty well I actually thought they would be a lot worse. Id go as far as go say its pretty comfortable. I have an EVO X with MCA blues on and they ride better than them.
So anyone thinking of buying MCA coilovers dont be too alarmed by the high spring rates.