KW and H&Rs are the ones most people go for. The KW V1s and H&Rs are height adjustable only. They are around the £800-£900 mark. You then have the KW V3s and ASTs which are fully adjustable (Damping, rebound, stiffness etc) but cost £1200-£1300.
You can then go even more expensive and go for the KW Clubsports. These are even more adjustable but include adjustable camber etc. They cost around £1800.
I went for the H&Rs on my 200 as I wouldnt really adjust the more complex ones myself so the extra money for me was a waste. They look bada$$ though:
My 200:
This ride height is just perfect for day to day driving (Speed bumps, multistory carparks etc). It can go a lot lower (But then the exhaust scrapes on bumps).