A band set with stones the whole way round has one quality no other ring has, which is that it looks the same from every angle and never needs orienting. There is no front. That makes it the easiest ring in the world to wear, since it cannot sit crooked and it reads as a continuous line of light rather than as a stone in a setting. Worn alone on a middle or index finger it is one of the few pieces of jewellery that manages to be plain and bright at the same time. Stacked, it does something useful too, adding light to a group of plain bands without adding a focal point. The stone size changes the register significantly. A very fine band of small stones is close to a texture and can be worn with anything. A wider band of larger stones is a statement and will be read as bridal by most people, which may or may not be what you want. Between the two sits the useful middle.

The real cost of the full eternity band is that it cannot be resized. There is no plain metal to cut, so altering it means remaking it, and that is a genuine limitation on a piece you intend to wear for decades while your hands change. Buy it very slightly loose. The half eternity, with stones across the top and a plain shank behind, solves this completely, can be sized within a size or two, and looks identical from above. It is the more practical purchase for most people and the reason to choose full eternity is comfort rather than looks, since a full band has no edges. Setting style matters for durability. Channel and bezel settings protect the stones and are the right choice for daily wear. Shared claw settings show more of each stone and expose the girdles, which is where chips happen. And a ring set all the way round will wear on the palm side faster than the top, so expect that side to need attention first.

Buy the half eternity unless you specifically want the comfort of an unbroken band, and if you do buy full eternity, buy it a fraction loose and accept it as a fixed size forever. Choose channel or bezel setting over shared claws for anything you will not take off. Keep the stones small if you want the ring to read as your own rather than as bridal, because scale is what carries that association rather than the shape itself. Coloured stones sidestep the reading entirely and are the underused version of this ring. What we would avoid is a full eternity band as an only ring for anyone whose hands fluctuate. If you take one thing away, ask whether it is full or half before anything else, because that single answer decides whether you can ever have it altered.