I recommend you get yourself kitted out with the Baglux system, Seb. The dedicated harness can stay on your tank indefinitely and the tank bag can just be clipped on and off. There's a range of bags including expandable ones so you can use the one appropriate for the occasion. They're not cheap but are very versatile and convenient to use. I've used them for all the bikes I've had since 1988 and recently got the tank harness for my Ninja.
Seb, I have used Baglux in the past and been very happy with them apart from the price. At the moment I'm using the Bags Connection quick lock on my Speed Triple, superb kit but again at a premium price. Take a look at
motohaus.com/acatalog/Pack_system
lol.iv just got bac from oulton.silverstone on thurs till sun nite,mite lose a few sleeps ther,then skeg thurs till mon,no sleeps ther,then of to oulton again on thurs,last bsb and party,mmm,no sleeps ther again,i love my bed!mite av to book me into rehab too,hehehehe.at least at skeg im in a bed not a tent!bring it on.x