The one HaiBike I tried was only a few pounds heavier than my touring lht. These days the battery tech with lipo batteries is so advanced that they really don't add that much weight. And if juice was an issue, I'd just carry a spare battery. They load up from any socket and at least the routes we've been on are stuffed with e-bike loading portals.
In terms of handling, I don't think you could notice a difference.