I've got a Bulldog Mini - go for it. It's a great lock, and yes, the small size will work to your advantage. It may only have a 3-1/2 star rating on the site, but that's just marketing BS: it's actually a really, really good lock. One magazine tested a bunch of U-locks, along with the famous Kryptonite New York Mini lock. The Bulldog came in second next to the $100+ Kryptonite.. both were virtually immune to prying with a crowbar. When they tried to pry the Bulldog using the frame as a lever they actually bent the frame while the lock stayed intact. The Bulldog also withstood professional, heavy-duty, ear-splitting power tools for 2 1/2 minutes, I believe. Which is very, very good.