the only bad thing about fighting someone who only goes for a headonshot, is that if you maneuver and avoid they extend to 3k, 4k, 5k and rinse and repeat.if you get around on them you chase them forever, unless you are lucky enough to get with in guns range and hit them to rattle their cage, then it is easy from there on.....
so most times you get bored, turn your tail to them and try to sucker them in and do a barrel roll defense or something another...... but most times you can't do this because they will lay in wait until you are in another fight or they will scream for 4 or 5 others to come and help them Maim you......
that is the only downfall of the HO...... it isn't because one can not defeat or deny a person trying to HO...
just my personal opinion - your opinion is your's