Shock Factory M Shock.
This was on my bike for 2 years and has done about 4000 miles. Excellent condition and hardly a mark on it. These shocks are well made and adjustable for preload and compression/damping.
It's sprung for an 80 kilo rider (without gear) but preload and adjustments will give it some leeway around that. Rebuildable and serviceable (by the factory) if it ever needs it.
http://www.shock-factory.co.uk/m-shocks-tecnical.html
It will go straight into a pointy without any alterations to battery box or tool compartment. Makes a huge difference to the ride compared to the stock shock.
£250 + post