As a thumb rule I use most drum tracks in mono. But not always.
If you want a Timbaland feel to the beat it could be right to have even the kick drum on a mono track or at least make a mono-> stereo reverb to it.
Stereolike effects on my drums are mostly made from mono tracks. If you place 2 mono claps a little from each other 25-100 samples and pan them a little left and right you get a stereo feel to it.
Unless the sample you load in is stereo, make the track mono. As a thumb rule. A hihat or percussion loop might very well be stereo. I have a mono button on my Presonus Monitor Station to quickly decide if/how much stereo tracks are while I audition them.
So, summing up the thumb rules
Mono mostly, but not for loops.
Make stereo effect from mono tracks.
But never say never; those Timbaland beats rely heavily on stereo, even on the kick on many of them.