I have to say that I'm not a big fan of the internal mufflers. In many cases, they loosen up over time and rattle plus I can never seem to get the right amount of muffling. It's usually too much or too little. That said, they are convenient and if they work for you, then by all means use them.
It's all subjective of course - I'm sure many folks out there don't like the moon gel or tape methods of muffling.
Also, it hasn't been mentioned here yet, but moon gels/sticky hands work on cymbals too. Need to tame that wash or bring out the stick sound on your vintage K or new Dream Bliss, stick a tiny little (nickel or dime sized) gel on that pie.