The tank bage is excellent. It is a standard Oxford Unit which splits into 3 sections. A bottom map holder.
A slim rectangular shoulder bag
An extendable top section which has straps to act as a rucksack.

I normally use all 3 together - like the photo on the right.

The normal fastenings are useless - it is designed for metal tanks - which the Pan doesn't have. Well - it does, but its under the seat - the 'tank' that you can see is actually a plastic cover for the air filter and carburettors.

So having bought it, I immediately stripped out the magnets and sewed up the seams again. I bought plastic rucksack-type buckles and nylon web straps which thread through the mounting point underneath the seat, and clip back onto the D rings on the middle section of the bag. The front mounting points have elastic webbing clipped onto the brackets welded to the headstock of the Pan. I have to tighten the main buckles quite tight - they pull against the elastic and keep the bag clear of the handlebars. Full movement of the handlebars is possible, but sharp left hand turns can be punctuated with the horn sounding as it occasionally presses in the button.

Removal is easy - I unclip the bag and leave the straps in place. The bag covers the petrol cap - so removal had to be straightforward. It really isn't a problem. Pity I didn't have a better choice of colour though. Still - my jacket is blue.

More pictures of this will be added as soon as I take them !