I've always been a fan of ZSNES over any other SNES emu, having used the original Snes9x even (I still remember the green GUI), but frankly the new kids that took over the project aren't of the same caliber as the original programmers. Never in my experience has ZSNES been so buggy. Games like Super Mario Kart, Pilot Wings and SMW2: Yoshi's Island, all games that used to work perfectly, now have problems.
SMK runs like crap, PW has crackling noises during the sky diving stages and SMW2's 1-7 level has a jittery background. Just a few things I've noticed several builds ago.
I'm sure there's more. Despite posts in their forum about these issues, none have been addressed yet. Blade And Soul Server Files. I know no software is perfect, especially emulators. But one of the key points of emulation is taking steps forward, not back. Hopefully the new guys will get things worked out. It's still my favorite SNES emu, but -1 for the step backward.