If it's a 1998 accord and this is the first time you would be replacing it? Yes definately get it done. Age matters just as much as milage. the rubber belts get brittle over time, crack and wear out. That is something that, if it breaks, will destroy your entire engine. Hondas have what is called an "interferance design" engine. That means that when the valves open, they drop down into the combustion chamber far enough that if the piston were to come back up that they would collide. This will only happen if the timing belt breaks. If the belt brakes the engine will start firing at the wrong times, the valves will be smashed to bits and it will need to be rebuilt.