Personally, I am using particular service for a long time and it has never dissapointed me. There are always people online who are ready to help (I hope they are not robots from Alpha Centauri) and who are able to explain in face to face mistakes you, as a player, are systematically doing.
For instance, I had problems of how to buy/found mounts and then asked Hotgear for help. And they provided me that help, thanks for that.
Moreover, I want to say, that I completely changed my opinion about boosting in online games. Who knows, maybe in one day I will become booster too? We will see.
Anyway, who is interested in boosting -- ask this service for help. They are great.