Craig, my experience is that you need to get them filled about every 2 to 3 weeks. Here in Michigan that costs me $9.00US plus tip. As I said before,they take getting used to, and you need to shape them to your liking, just as you would any finger pick. For me, I file them down to just slightly longer than my finger. If I leave them too long, they get in the way.

As to having to replace them, my experience has been the same as Jed's. You don't need to. The old line about the nail breathing also isn't so. The nail doesn't need to breath. If one is silly enough to pull them off, then the nail underneath will be weaker because you have pulled a layer off. Also, they smooth your existing nail before installing them by grinding it. If you don't like them, you will have a thinner nail until the real one grows out in a month or two.

Mick