Hmmm, I had been using the slow freezing method, but after reading the article and these posts, I think I will switch to the quick temp drop or the alcohol. I guess the selfish advantage to the slow freezer is that I don't see the fish dying. But if it is more humane and efficient to do the alcohol or quick temp change, that's what I'll do from now on. Sometimes you really have to do it. Once I had a fish whose stomach exploded out of its body (a greedy guppy), but it stayed alive. I figured there was no way it could be happy and and no way to fix the problem...