I believe that tips wax and wane in popularity for reasons that have nothing to do with the actual performance of the tips. When a tip is first introduced, especially if it is from a well known company, lots of people try it out and it may become the "hot" tip of the season.
I was talking to a cue maker the other day, a guy who puts on hundreds of tips a year. He told me that he hasn't put on a Sniper THIS YEAR, and this is a tip that was often requested a few years back. He says he is now putting on more Kamui Black tips than anything else by a large margin. There's no question in my mind that Kamui Black is the "hot" tip right now.
But back to the Everest vs. Sniper question. Obviously, they are both fine tips and choosing between them is mainly subjective. Snipers may be harder than an Everest on a Durometer, but they SEEM softer, especially when first installed, because the sound of the hit with a Sniper is more of a subdued thud than a click, clink, or ping. So some people reject them as being too soft when they really aren't a soft tip. I have shot with Everests on several cues, on an off, for a few years and also shot with Snipers on several cues. If I had to pick just ONE to use on every shot from here on, I'd pick the Sniper. I like the softer hit sound of the Sniper and believe they have at least the same "grab" of the cue ball as an Everest.
BTW, the two cues I have been playing with most recently have neither a Sniper nor an Everest tip. One has a Triangle tip I put on myself -- I got lucky here because it happens to be a great Triangle tip. The other has a Kamui Medium Soft, one of the brown Kamui tips.