I’ve actually used it twice for my elementalist and my engineer. (One from the last expac and the other from the store)
Already had played an elementalist up to around level 40 or so but found out i didn’t really like the looks so decided to redo and use the boost.
Engineer i had only played to around mid 30’s but wanted to try it as another race so a delete, redo and another boost.
Already have 7 level 80’s i leveled up normally so i am familiar with the game somewhat.
My suggestion is if you want to try a boost, at least play the class for a while so you can get at least somewhat familiar with it.
Been seeing a lot of players who seem to have no clue to what they are doing sometimes…lol