Love my S18. It serves all my needs and I have no plans on getting a new one any time soon.
But I gotta say, not trying to be judgemental, this is is just me, but I feel like if you want to go much faster than 20-30mph, especially on the road, an EUC is a really poor choice. They're just not very safe at high speeds compared to other options like an ebike. And of course, if I'm going to be going fast on a powered bike on the road. a motorcycle will go even faster and often will be safer due to the better suspension and bigger tires.
Anyways, I have EUC's, eScooters, eBikes, BEV car and a motorcycle license (though I don't have a street bike at the moment) so I have options. Everyone can make their own decisions when it comes to issues of personal safety that don't affect other people. Wear a helmet or don't, ride a 50mph EUC or don't, you're only potentially hurting yourself and most of us are old enough to decide for ourselves. :-D