Well, if we're speaking strictly of popping my favorite is definitely needle popping for latex and scissors for mylar.
An average 3" or so sharp sowing needle usually works best. I love it when the person popping them is playful and teasing. Not too much nor too little. i.e., doesnt pop too many too fast but also doesn't take more than 15 secs or so to pop them. That way with a bouquet of a dozen latex lasts long enough to enjoy but short enough to feel controlled, and helpless.
With mylars I actually prefer deflation by snipping the valve. Just a simple, quick, clean and innocent cleanup.
But popping them with scissors is satisfying too.
All I all, While i have my favorite(s), I love popping and seeing balloons popped many different ways. *^_^*