Just so you know, this is kind of a rambling post for whatever reason, but its my input, as 2 of my best friends have these skis (one with One Lifes, other with JJs)
If you want input from somebody who has skied both a lot, pm Fishgills
One of my friends has JJs, and absolutely loves them. His favorite skis ever, he uses them for everything (except park). He then found a great deal on some one lifes, and loved them also, but then sold them to my other friend. So now one has JJs which he loves, and one has One Lifes, which he also loves. The One Lifes are stiffer that the JJs by quite a bit, but seem just as nimble. The wierd sidecut of the JJs lets them turn super easy, you just think turn, and they do it. The One Lifes require a little more input, but are still great. you will be happy with either, as they are pretty similar skis, it would depend more on what conditions you are in. If you ski trees more, I would go with JJs, because of the small turn radius, whereas if you ski bigger, more open terrain, I would go with One Lifes. Not to say that the JJs cant charge, whenever I have skied them they have never wheelied out or anything, but they are better suited to tighter spots than One Lifes. JJs are more jibby and turny, whereas One Lifes are stiffer and cut through crud a little better. I have also heard that One Lifes are super fun in the park, which may weigh into consideration. JJs arent as good in the park, because they have thin sidewalls which are less durable. Basically, you'll be happy with both, it just depends on where you ski and what kind of skiing you do with them. I