If you find the medium underrated, it's due to the fact that due to its engine design the amateurs who play against it often get cocky and the engine then, despite saccing it's knight meaninglessly 15 moves prior, will 100% of the time notice anything that gains a rook, queen, or a forced mate up to 4 ply.
The hard computers may seem underrated because calm players who don't 'get cocky' often can get good results against it multiple times in a row (rating boost against an engine they have 'figured out'. On the other hand, it is very easy to 'get cocky' and lose to it.
I'm finding the medium (1200) level to be overrated, far easier than players in that range I've met. The hard (1600) level I'm finding the opposite, it seems underrated.
What do you all think of the 1600 rating?