Well, I can't vote so I'll post my opinion. If I had to pick just one, it would be a plain edge as it is capable of fine cutting that a serrated edge can't do. But overall, I prefer serrated blades. They don't have to be sharpened as frequently and they do a much better job on most of the tasks I use a knife for. Additionally, most serrated blades have a short fine edge section that can be used when serrations would not be appropriate. This is especially true of Tanto blade shapes such as CS's Voyager line where the edge between the primary and secondary points is a fine edge. I find this to be highly usefull and perhaps the closest to the "one blade for everything" concept. Still, there are a few tasks that I wouldn't use such a knife for. So if I had to pick only one, it would unfortunately be a fine edge blade.