Originally Posted by
prathmann
The mini size makes it harder for a potential thief to insert a jack and pry the lock apart. But if you're in a relatively low-theft area and plan to lock up the bike in a variety of places I'd opt for the full size type instead so you don't have to search for just the right size object to get the lock around.
This. I have a u-lock which is about half an inch narrower than most other u-locks and this makes locking up my bike
significantly tricker even though I have a bike with very narrow rims and a narrow aero downtube. The u-lock only looks marginally thinner than most others but this makes a giant difference; I used to have a wider lock and that was much easier to use. Think carefully about what things you might be locking your bike to.