[yuppie]

it depends from which drum sound you want. If you are going to mic a jazz-style drum you need a large and balanced room as you would mic it with two ambience mic away from the kit;
for pop and tight drums you can reach a good sound also with a small room but it could be preferable not to use ambience mics, mic the kit very close to any piece (cymbals too) and add some acustic baffles all around the drums if you don't like your room response, then add you favourite verbs and first reflections on mixdown.

matteo