It's hard to argue with a product that works.  Killed a rat in the first night and I'm expecting to catch more.  I purchased the 12 pack and set up 6 under our house where I've been hearing the critters.  I used peanut butter on half of the traps and a small wedge of chocolate on the others.  One of these had chocolate and peanut butter.  When I checked my traps this morning I could see one of the traps with chocolate and peanut butter had the chocolate removed and the peanut butter licked down a bit but not sprung.  The other trap contained the dead rat (about a 6" rat) and that trap had one of the other sticks of chocolate.  So it would seem they are going for chocolate set traps more than the peanut butter.  But it's early days and I'm expecting to kill at least a few more.