you all are correct, but one very important thing is missing...on ldon raids, everyone in the raid must also have atleast 2, successful ldon missions from the zone you are wanting to raid.. ie 2 sucessful ldon missons in mistmoore ect.. also the ldon raids not only have a min level, and prev mission success requiremnt, they also have a min number of people before you casn even request request a raid misson.
now for the differnces, for one, you can only do one raid in each zone twice every 5days i think or there abouts, secondly, the drops, the loot whereter it comes from a mob, or from a chest is going to be way better in a raid then in any reg ldon normally. traps are more deadly, and more names will appear throught the raid then on a reg ldon venture.
ok to sum, what make ldon raids differ from reg missons, is the min level requiremnt, the min success requiremnt, the min raid success in a week requirmnt, the ammount of people neded in order to begin the raid from the raid merchant. k ive said my peace best as i can.. hope this helps..