In my experience, Hahns are great Macaws to start out with. Again in my experience, they tend to form strong bonds with one person. You'll have to work with one from a very young age if you want to break them of this. Mine is inexplicably more friendly with men than women, and can be quite aggressive, though I expect this has to do with his two previous male owners and being a solitary bird for much of his life. As a species, though, they are very individualistic and energetic, you never know how they're going to behave until you've had them for a while. They have a strong bite for their size, but are unlikely to cause the sort of major damage that their bigger cousins can inflict.
As far as talking goes, Hahns are fairly vocal, but I wouldn't expect one to pick up more than a dozen words or so.
As with all parrots/macaws, personalities and behaviors can vary, sometimes greatly. If you are their first human, they'll tend to pick up quirks specific to their relationship with you.
As much as I prefer rehoming birds to buying from a breeder, I'd suggest you go with a breeder and get one young, as they can be unpredictable if they've had previous owners.
