Regarding the sideslip limitations, most other helicopters do also have entries in their POH/ Flight manual. No manual will specifically write that sideward flight above certain speeds is prohibited. Rather they state that successfull sideward flight has been demonstrated up to a certain speed.
To a previous posting by eurcocopter, no offense,but you probably don't know either how many times you have been close to something that could have killed you in any other type of helicopter.