Do sharp cutting blades on my ride-on mower make a difference?

Yes, absolutely! 

Dull or damaged blades will leave a jagged edge on the blade of grass which will brown and it highly susceptible to disease, especially in wetter or humid months. Dull blades will make your engine work harder and the end result will be worse. 

Once sharpened, the blades then require balancing to prevent any vibration. Your service engineer should sharpen your blades during a typical annual service but it’s always worth asking to ensure this is done.