Many of the questions I am asked on a daily bases are about vinyl liners, and a lot of those are about beaded liners. I will go over a few of them here in hopes of helping you with your own liner installation.
Beaded vinyl liners are liners with a hard plastic lip molded to the top. This hard plastic is the bead that is inserted into a bead receiver. The bead receiver hooks over the top of the wall and the liner is installed from inside the pool. This can be done without removing the top rails. These have been around a long time but are just now gaining popularity. Many pool packages are including beaded liners as standard equipment. Many years ago they were an expensive add on.
The drawbacks to a beaded vinyl liner have to do mainly with the fit and how they install. In many cases the liners are just too big for the pool. On a warm sunny day it is easy to work your fingers numb inserting the bead into the receiver, all the way around the pool, only to find out you have an extra foot of liner. You now have to take the liner out, most of the way around the pool, and reinsert. This time bunching it as you go. Or the reverse could happen. You get to the end and need an extra foot. Take it out and stretch like crazy the second time.
The second critical area regarding fit is the sides. The bottom must be as smooth as possible. That is a given. That means that all of the excess liner is smoothed to the edges of the pool. At that point, you have no way to adjust the amount of liner that goes up the wall. If the liner is on the small side, the liner may be 6" from the pool wall when it would need to be inserted into the bead and forced to stretch the rest of the way. If you are working in strong sunlight this is the best case scenario. The liner will stretch the rest of the way making a nice tight fit. If you do not have direct, warm sunlight your pool walls may buckle before the liner stretches.
The other scenario is you smooth the bottom and you have an extra couple of inches of liner going up the pool wall. There is no way to lose this extra liner. It just wrinkles. You can suck the air out with a vacuum but you will still have wrinkles. If you let the water push all the excess liner to the top there is no downward pull on the liner to hold it in the bead. Unless the liner fits just right, you are just stuck with a mess.
For more about beaded vinyl liners visit the installation page.