Hi,
The Essence only fits on the Essence bracelets and it is different because they don't move around onthe bracelet. You fix them to the spot you want them and I think they stay relatively well in that same spot. I don't have one myself so can't say for sure but I think I read some ladies saying they move a tiny tiny little bit by the end of the day.
Do you keep your bracelet in a non tarnish pouch? You can ask for one at the Pandora store and they should give you one with most purchases, or free if you tell them your bracelet is tarnishing. I get one everytime I buy anything. Also you could buy a Pandora polish cloth, they sell them in the store, just ask one of the salesladies. They cost about 5-7$ depending on where you are. So you just rub your bracelet with that once in while and it takes the yellow and tarnish right off. Or you could get a baby soft toothbrush and some very gentle dishwashing liquid saop (like Dawn) and gently brush your beads in warm water every once in a while. Then rinse them very well and lay them out to dry on a paper towel