I've been using DrumDots on my snares. They are clear, reusable, and very functional in controlling ring:
In the past, drummers would remove the internal mufflers because they would often rattle loose and you would have to take the head off to replace them. Plus, it's an unnatural action - the head is pushed down by the stick while the muffler is pushing up against the head. Many found them to be too tone-altering.
Also, extra holes in a drum is a no-no!
Hope this helps - cheers!