the HD3/white is essentially a repackaged HD1 + wifi and misc improvements.

the HD3/silver is essentially a repackaged HD2 + wifi and misc improvements.

the HD3/black is something new.

you're not the first one to be confused by the naming convention.

IME, the HD2 does better than the HD1 at catching plate numbers, especially after dark. that said, it's still not what i would call "good". it seems like the HD3/black is better, but i can't comment on whether or not it's "good".