Well, I was gonna go for the Stahlkoffer panniers for the F800GS which comes in at £399+vat which is a very good price, but I am now reconsidering and maybe I should go for the BMW aluminium panniers instead. I am not sure how much more they will be, but I think it might be worth it.
I have emailed the dealership to get some pricing as it might be the deciding factor.
Thus far, I have been traveling without any panniers, just 2 waterproof rollbags/duffelbags on the back, but I think for any serious long distance trip, the panniers are essential. You can pretty much pack everything in there, strap stuff to the back (i.e. petrol containers) and on top (tents, etc..) and your done ! I think they are also a little bit more secure than soft luggage, you can use it as a chair at the campsite or even a little table … definitely something I need !
I will report back on the price and my decision regarding the panniers …