Not too many Poms (or at least admit to it, especially now!!) on this site Milkman, so your aside comment probably was lost to most!! LOL
Watch out when buying the tankbag that it has good side clearance. I have a GEARSACK tankbag with extra capacity zipper if needed, a handy feature. However clearances are tight especially with the 65's lower Euro bars, and on full lock it has a couple of times activated the kill switch, embarrassing if executing a U turn, which I wasn't at the time fortunately (to the US contingent, our U turns go to the right!!).
Make sure it also has a generous waterproof map reader pocket, mine has a full width one and I use it to hold my PDA with GPS receiver attached and a map to one side. It also has a large zipped waterproof pocket on the back, right in front of you, that will hold a wallet and phone. Handy in that you don't have to open the whole kit to get to them. I opted for one without magnets as it's lighter, and you get more bag/features for buck if you aren't paying for expensive magnets. The harness has large clip buckles so it's very easy to unclip the bag, not as easy as magnets, but hey, what are you going to do with the extra ten seconds anyway?? Attaching the harness is only a 2 minute operation you do at the start of the journey, and I've found it stays secure the whole time.
Bill...................................;-)