I've ridden both Energicas, the Zero FXS, Zero DS, the Alta SM, and Harley's joke. I've also ridden some modified race built Altas.
Even the race Altas had a linear and smooth power delivery. The bikes are just not exciting to ride. They're reasonable, but I wouldn't go beyond that. The Zero could do a burnout at exactly 1 mph. That was giggle worthy, but a parlor trick at best.
Even the sport bikes still felt like appliances. Completely adequate appliances, allowing me to completely disengage from the riding experience and become curious if I had any new text messages or emails.
Basically the motorcycle equivalent of a nap.
This comes from a guy who thinks the NC700X DCT is the best do-all bike ever.
It's also worth pointing out that all of my e-motorcycle experiences required the bike be trucked to the riding locations, as they couldn't do a round trip for the recreational riding without a mid day charge. The only charge facilities are standard 110v outlets.
Something like the Zero DS could do 40% of my errand trips. That's not exactly worth registering and insuring the bike, even if it were free. No current e-motorcycle option could facilitate my recreational riding.