According to my Mac dealer, Snappy's (at least anything up to a KRL or quite possibly a KRL) are fairly the simplest to crack along w/ Matco's, Cornwells and Craftsman's. He said the locking setup on a Macsimizer however, is probably the hardest to thieve due to however the bar's and lock rods are positioned(he said he wasn't being biased either, so I'll string him as honest as he usually is with me). He's had to pop some before to do repo work b/c tech's lock their box, obviously, especially on their days off while business is a boomin'.
Don't know the 100% truth to this, but it's still interesting