Hello - if you get a quote for the official Pro Drive Brera S suspension parts, you will get a shock - including original parts and labour you're looking at £2,500 to £3,000!!!!!!
I don't think it matters too much whether you have the 18"s or 19"s, for example there's only 10mm difference in the width (235mm vs 245 mm). Bear in mind that tyres for the 19"s are very expensive (£200 each), they will be slightly less comfy and maybe slightly noisier.
Also bear in mind the Brera S can be a little tiring over motorways/distance, though the handling is very good.
Instead of the expensive official S suspension, people on here have either replaced the shocks with aftermarket kits such as the Bilstein fully adjustables (£1000 - £1300 for the parts plus maybe £400-500 labour), or left the shocks alone and changed the springs to something like the Eibach Pro Kit (£180 plus £350-400 for fitting).
Personally, I went with the Eibach Pro kit and am very happy with the combination of handling, road feel and ride comfort. Less harsh than an S, can still cruise for a long time on motorway. Also around 25mm lower than normal, so the car still appears to be stock, but looks that extra bit meaner
On the 2.2 you probably don't need to fork out for the fully adjustable dampers, but they would be a fun toy (can adjust for track days/motorway cruising etc).