I have a 90hp 2 up. For me, it's plenty of power. I didn't think it would be, because I'm the type that almost always wants more power HaHa
I ride mine in the Gulf of Mexico and inter-coastal waterways and for the most part it's too wavy to keep it at full throttle for a long time. I mostly use full throttle in quick blips for messing around doing donuts, jumping waves etc. The Spark is light so it really hops a lot even in light chop.
If you're riding in a calm lake and want to achieve better top speed numbers that's a different story.