How tiring is riding the bullhorns?
I use bullhorns on my fixed gear commuter bike, and sometimes get some hand fatigue/numbness because of the position.  As with everything, everyone will have different experiences because physiology.  But it's been my experience the most comfortable position is in the curve forward.  The forward position is close in comfort to riding on the hoods on normal drop bars.  If comfort is your aim, you will probably get more mileage(get it?) out of better tape or a nice set of gloves.