[markw10]

I want to purchase a Kensington lock which I'll use with my MacBook Pro and likely one also for my iMac and possibly Mac Mini.
It appears where they plug in in the side is simply plastic and they would be easy to rip away to steal a laptop but in general on Macs and other computers (I also have an Acer laptop I want to use them with) is there something that is steel reinforced inside to actually make it stronger? How easy is it to break off these locks?

[mduell]

Those locks aren't terribly hard to defeat anyway... they're more of a deterrent (so the thief steals a different computer) than protection.

[ghporter]

If you attach the lock according to the instructions (and you don't use one of those cylinder-key locks that a ballpoint pen barrel can unlock), then you have a definite chance of protecting your computer. Of course you have to use the thing correctly; locking it to a chair or the end of a table leg is dumb. But who's going to buy a "used" laptop with the lock slot broken out? It can be done-not easily but it's possible-but making the effort is a big deterrent. The thief may pass your computer up and look for one whose user didn't bother to lock it at all, as mduell says.

[mkral]

I use one of the kensington locks all the time. It's actually pretty good at securing the computer. Even on the plastic ibooks, it takes quite a bit of strength or leverage to bust it off the computer & then you'd have a computer with the side broken off. Plus it makes it obvious that someone is trying to steal a computer. The ones with a keyed lock (as opposed to a combination lock) are pretty secure & hard to beat.