I think it depends on where you live and ride. Where I live and ride (on the outer fringe of Indianapolis) there isn't too much theft or vandalism for bikes. I commute daily year round, and also run errands like libary, post office, hardware store, etc., I just take a really long cable and weave it through all the bits and secure to something solid, like a bike rack or lamp post. Toughest item is if you want to also lock up your panniers instead of taking in. I view this kind of lock-up as a deterrent to the casual thief, not much will stop somebody who's been shadowing you with intent to take. If planned theft is your concern, then multiple U-locks so that they have to take time to break more than one. I'm not on a trike, but I expect the concept is the same. Something like a long cable should be OK in Reading PA (I lived in LancCo 1998-2004), your trike should be safe with almost any kind of lock, what you'll find instead is that small bits periodically disappear or are damaged (mirrors, computers, lights, fenders, etc.) due to the random person who is just mean, sort of like having your car keyed down the side. I also find lots of people think its perfectly OK to climb into your bike to see what the seat feels like, or to have their small children run your shifters and brake levers for several minutes while they do something else. When in doubt, take it inside with you and leave at customer service with a minimal lock.
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Longbikes Slipstream