So I'm facing a broken rear spring at the minute and an NCT fail so I'm curious as to what I should do for a repair. Some lowering would be nice, I've no real opinon on whether I want the ride to be stiffer.

My OEM option is to replace both coil springs with genuine BMW - that'll set me back €300-€400. I've been reading that when replacing the springs you should also replace the shocks; is this true? The car has 103k miles on what I'm assuming are the original shocks so is it time for a replacement? I've no idea how long the rear spring was broken - up to 10 months since it passed the NCT last December.

Another option I'm looking at is a swap to a coilover/true coilover setup. It's not a track slut or anything, I've only took it to Mondello once and nearly shit myself :P It'll probably end up there again though at some point but not regularly. What would a coilover setup offer me over factory apart from lowering?

I've been reading about potential issues swapping to coilovers on the M3 with lots and lots of people recommending some reinforcement plates, claiming that the swap will put a lot of pressure on the sheet metal - anybody have any opinions on this?

Are there other options I'm forgetting? Would an aftermarket coil with factory everything-else achieve lowering while making no other sacrifices?

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