If I played their kind of music I'd stick with a 4-piece too. I'm sure there was some guy who grew up in the late 1800's who looked at the evolution of modern trap sets and said something to the effect of "if a cat gut marching snare with skin heads was good enough for *insert name of civil war era marching snare badass* then it is good enough for me." And if that's what you're into, then by all means, have at it.
Well, that's your Buddy Rich fantasy. Mine goes more like:
He would be too busy yelling at me about how I fucked up this or that in my kit design or how I hold my sticks all wrong to even get to the point of playing. But let's assume he overcomes that and does actually play. He would find that my stuff is angled "all wrong," causing him to play some "clams," at which point he would immediately start yelling again for having played said clams. Then John Wayne would show up and they would get into a fist fight, kill each other and immediately come back to life as zombies. They would go on fighting in an endless loop because they grew up in an era devoid of proper zombie lore, each of them not realizing that you have to shut down the brain to kill a zombie. You can also poor salt in their mouths and sew their lips together, but who ever has time and materials for that? Best to stick with a shot gun... or a chain saw... or maybe the ever conveniently placed helicopter blade. The trick with that one is a you need to kite the zombie into the path of the blade. Oh, and you do need to have access to a running helicopter. But if you can pull it off, you'll pretty much be the Buddy Rich of zombie killers.
Ok, seriously. Buddy was great. Perhaps the greatest, and I love his playing too. But let's not start attributing words and actions to corpses so that we can feel better about our personal choices, or more comfortable with how someone else's choices sharply differ from our own.