I'm leaning (no pun intended) toward the YikeBike. It
seems to have more stability and control due to sitting and holding something vs. balancing while standing with no handles.
And I could be wrong, but the YB also seems more promising as a company. They've expanded impressively in the years I've watched them.
A YikeBike rep called me while in NYC to try one, but we never connected for a trial
That's the only way I'll plop down $4k+ for one, so hopefully another rep will contact me.