Hi Adrian,
You´re right, its a good lock but too heavy to be carrying around in the pocket. Dunno about England but you need a second lock here in Sweden as an insurance requirement.
I never thought about using the case, seeing as I shelled out on the proper holder, without off course checking to see where it might fit. I found a potential spot where the frame cradle comes up under the tank. There are 2 bolts there joining the frame together, but I am a bit wary of messing with these. Failing that it´ll have to be some bodging or back to the stretched pockets.
Cheers
/Craig