An Auto level like these
here are fine for transfering levels across a site, but as Hanalike says they do not do vertical leveling or angles.
Its horses for courses, an electronic theodolite is more flexible and does a lot more, but you pay more for one. A Theodolite can also be used to triangulate and traverse area's. What you need to ask yourself is would you get the use out of paying the extra for a theodolite over an auto level, or is it something that would only be used once every blue moon?