As it says in the yam handbook...
The service intervals provided in the Mainte- nance Chart were developed based upon “typical” use that includes operating at varied speeds, with sufficient time for engine warm up and cool-down, a medium to light load, and an average cruising speed near the 3000 to 4000 rpm range. As with any engine, however, if your normal operating conditions are different, you should consider service more often than shown, especially how often you change your engine oil and gear oil. Ex- amples might include extended wide-open- throttle use or long periods of trolling or idling, carrying heavy loads, or frequent starting and stopping or shifting. More fre- quent maintenance will often pay off many times over in increased engine life and great- er owner satisfaction. Consult your Yamaha dealer for additional maintenance recom- mendations.
...The choice is yours.