Well fitting was pretty straightforward - took about an hour from start to finish and nothing especially difficult just obvious unbolt and replace work.
Having ridden them on teh out the box settings for a day or two I felt the difference - less jellyish over speed bumps and bumpy corners but I didn't really have a chance to run them much before the ride to the hog roast.
Fully loaded with the pre load wound up to the max the bike handled really well driving through the twisty B-roads. It felt well planted and secure which was a definite improvement of the old OEM shocks.
The big test was the off rad at the hog roast so everything was unloaded and we headed off trying to keep up with a DRZ400 and a CR450 .....

The Ohlins were spectacular off road. The absorbed everything I could give it. The bike was transformed and I never once bottomed out the suspension which was happening quite often on the OEMs.
Final test was a week of touring around Wales following the hog roast. Overall verdict is that I definitely need to replace the OEM shocks. They were working but clearly at the end of their life after 80,000km of use in all conditions. The Ohlins are a very worthy replacement and represent value for money against a replacement OEM set.
The down side is I don't think I will be able to get the front alternator cover off to get at the poly-v-belt without removing the front Ohlins. They are much bigger than OEM so there is no space around the shock. I'll find out when I get round to needing to do this some time in the months to come.