I have chronically dry lips and am constantly trying (and reviewing!) products to help. I don't know the cause of them, and I've never found anything that made a longterm difference (many thanks to everyone here who has given me recommendations though!). At one point in time, Jack Black, AmorePacific, and Hourglass lip oil have helped, but even those don't work anymore. I held off on trying La Mer because, you know, $65 seems a lot for a balm. But then again, when you look at how much I've spent on products that don't work, I realized it was better to try La Mer, because if it worked it would save money in the end (or at least that's how I justify it). I wasn't extremely convinced it would work, but to my pleasant surprise, it has saved my lips. They used to be so dry, cracked, and peeling that I couldn't wear lipstick anymore because it applied so unevenly. So mostly I've had to stick with glosses, which is a bit of a bummer because I love lip products.
This balm gave results almost immediately, and my lips look semi-normal again. I realize it's unrealistic to think a single product could fix the problem, so I'm just happy that my lips don't feel painful, have become more smooth, and that I can start to wear lipstick again!
NOTE: I suspect if your lips aren't very dry, this balm may not be worth the price. Before having this chronic issue, I got by with Jack Black just fine. But, if you're in my position, looking desperately for something to help when no other product has, this may be worth a shot.
I do wish it came in stick or tube form, rather than a pot, but oh well. I think the effect is worth it anyway. I suspect the jar will last at least 3 months when used every day, and I do plan to repurchase when it's used up.