I've had Eibach Pro springs on my Brera (2.2 SV) for a few days now and thought it worth while giving it a review for you here as it is available for Brera and 159 (and probably spider though i haven't checked).
Virtually eliminates nose diving under braking and nose rearing under acceleration, and totally eliminates body roll and wallow. Actually makes the car more comfortable because the car stays so flat all the time.
Lowers the car by 20-30mm, which you can see when you look at the wheel arches - rear arch looks perfectly filled by my 18" wheels. Front arch slightly less full looking but looks good. Car is definitely a bit lower. So what happens witht the dreaded London speed bumps?
It actually clears speed bumps BETTER than the original suspension. Clears the speed bumps the original suspension used to, plus all the ones it didn't!! Clearly this must be due to the stiffer springs, and the large reduction in nose diving/pitching.
So the springs are stiffer, and this means you get more feel through the wheel and pedals. This is nice, you can feel the corners much better. Haven't flung it round too many corners but already have more confidence and am really enjoying cornering in it. Some of you may have noticed on previous runs me bottling it round blind corners on the original suspension
So if it's stiffer, what about the ride comfort? Well surprisingly, I find it very comfortable in town. You can feel more but even my wife agrees there's no loss in comfort. Presumably this is because the dampers are still the original comfy ones, and the new springs are simply higher quality.
What about at speed? Well once you get above 90 mph there is a slight increase in vibration, but to be honest it's not that big a deal and still doesn't really spoil the ride.
You can definitely feel the speed more, whcih is nice, because to be honest 100mph in a standard Brera felt like about 70mph in an ordinary car, and likewise 45mph felt like 30 mph which is in a way a bit dissapointing. I think this is a large part of the reason why some people always considered the Brera slow, and yet no one complains that the Brera S is slow, despite having the exact same engine. It's all down to perception of speed being greatly affected by the suspension.
In summary, I LOVE them. Makes the car much more sporty, but not at all uncomfortable. In my view, the perfect balance between a Brera and a Brera S.
Price is good at around £180 inc VAT for the full set of springs, but budget twice that for the fitting.