i always carry my mini in the back pocket. and through the years, I've accumulated a number of u-locks, so they're just hanging out at the regular places I park my bike (school, gym, work). that way I use the mini for the frong wheel & frame, and the secondary (larger u-locks) for the rear wheel & frame.

but mini's rock... I feel totally comfortable using just the mini with the front wheel and frame as long as visibility is decent.