Security.org recently released a security alert regarding Kensington lock mode 64038 being insecure.
In plain english, that means the lock can be picked with a Bic pen and a pair of scissors with about a minutes practice. Whats more, since the lock-pick method doesnt damage the lock or the cable, the Kensington challenge of "if someone steals your laptop, we will give u $1500" does not apply !
I just changed my mind about buying one :)