Count me in for a class action.
Mine happened after warranty but was caused by the dealer not aligning the motor in the ski properly after replacing the hull (that's another story). Long story-short if you own a Spark you better learn how to work on them.
I have two 2015 Sparks; one striped the splines and both rusted at the seal area causing leaks. The crank shaft is now almost half the price it use to be (+/- $800) so I'm doing mine myself now.
Word to the wise...if your skiing in salt water change the output sleeve seals every two years. Check your motor alignment during this time if you a do lot of wave jumping or your motor gets removed for some reason. Sea Doom engineers allowed for to much linear travel on these drive shafts. I'm guessing that hulls flex more than fiberglass.
One more. Don't mix your antifreeze; I'm finding out now during this tear down that the same dealer above top mine off mixing variants of antifreeze. I'm glad I caught it now.