I have a pair of HM-1s and totally love 'em...especially for drum OHs.
I agree with Tiny that they have a wider cardoid pattern, but I find this works just fine with the "Recorderman" or Glyn Johns type setups.
I find they can smooth overly bright and brash cymbals, and render toms very very well... warm, fat low-mids and mids. Smooth and round is how I would describe them.
I have used them as OHs for tracking hard rock, reggae, and funk/r&b stuff and been quite happy with the results in nearly all cases (though I tend to be pretty easy to please
And they are cheap too...at only 129 bucks US each!(but sure don't sound that way) Check 'em out at Kel Audio