Well, I got to ride Luke's electric bike yesterday -
BTW, I like the name "Luke's Lectrics" with a nod to the classic brand, Lucas Electrics.
His bike is really a functioning bike. Throttle control was very predictable, and he spent some time going slow, through a trials sections, just to see how it would go. When you want to go..and you twist the throttle..it just GOES!!!
Because he built it on a real dirt bike platform, and he's managed to keep the weight where a similar gas MX'er would be, it just feels right. Battery life was shorter than he would have wanted...and he mentioned something about slop in the throttle, but I didn't think it was an issue....Luke has done an amazing job with this thing.
Here's some video of the bike in action: