I have Oxford disc alarms and chains on both my bikes, I run the chain through the back wheel and lock it to the frame, the older of the two locks is almost four years old and still on the original batteries, It is used even when the bike is garaged so that's whenever I am not riding it 24/7 for almost 4 years, recently I had to leave the bikes for a couple of months parked in Central London along with my mates bike which had an ordinary but very tough lock, drunks leaving bars and clubs used to get on the bikes and muck about and several times I came out in the morning to see bikes on their sides with smashed levers, mirrors, screens and fairings but luckily both mine got left alone, my mate wasn't that lucky he had to replace a mirror one night, a mirror and indicator on another, his screen mirror and indicator on a third and finally caught two lads trying to nick the bike even though the back wheel was chained, I was lucky and got a place to park off street but as he still has to park on the road so he bought an alarm lock 3 months ago and hasn't had any problems since.