Appealing though the underseat explosive option is, I'm with BBrown - let them have it, save yourself injury and aggro. Spend your money on a tracker (if you think the Met will support you by recovering your bike once it's located - debatable from what I hear).
Going a teeny bit off topic - up here in t'broad acres a farmer friend of mine agreed to have a police "sting" quadbike parked on his farm - it was duly pinched, in broad daylight, while he was in. Police informed, Quad tracked to Bradford (where else?) and it and
six other stolen Quads recovered, two arrests. Satisfying.... Farmer Palmer's only regret was that he was warned off using his 12 bore if they came
(defeats the object of the sting apparently
)
Also slightly off topic - maybe this should be in "what gets my goat" - a few years ago, I had a bike stolen from my house. I discovered the theft minutes after it had happened, so figured "dial 999". Response from the bloke at the other end? "fine sir, can i just take few details before i put this out? Date of birth? And how would you describe your ethnicity sir?" Absolutely foccin' unreal! Guys raggin' my bike down the road, and I have to decide whether I'm white British or white other (or just red with rage?)
Needless to say the bike was not recovered until the scrotes got bored with it five months later and left it, trashed, behind a pub in Bradford (where else?)