Originally Posted by
FBinNY
I don't know what problem you see. I've carried camp stove fuel in just about the same place for decades and never had a problem.
However, the OP's lock extends pretty low, so I expect that he needs extra care if there are old style speed bumps where he rides, otherwise I'll venture that he never has issues with it.
It doesn't extend lower than the pedals when they're vertical. It doesn't get nicked even when riding up onto curbs.
Besides using otherwise unused space, I really hated having the lock on the top tube or seat tube because it's free to swing on the mount. It would sometimes hit my legs when pedaling which was annoying.