It's saved me an absolute fortune. In fact after owning it for a month, my wife wrote off my car. We just took the insurance money and didn't buy another car going down to a one car family.
I have a gold standard D-Lock that is side mounted on the frame (weight not an issue) that I use when parking up. There is also a dutch style rear wheel lock mounted to the frame I also use. The battery has a key that keeps it locked to the frame. The head unit for the eBike display is removable and I take that with me whenever I leave it locked up making the motor unusable.
Basically you're trying to steal a 25kg (55lb) bike with multiple security features and relatively unique electric parts that people would be wary of buying due to lack of guarantees.
Sometimes if I'm popping into a shop/café, I use the bike stand, lock using the dutch lock, and just take the head unit off. I'm guessing somebody could pull up in a van and just lift the bike but the opportunistic 'snatch' is so not going to get very far.
(Though if you don't need the e-thing 310€ will get you started)
As a way to get from A to B quickly, nothing beats them in a city.
I did an Air Pollution piece for the BBC comparing exposure of somebody walking, cycling, and driving in and around Bath. As the cyclist, they told me I was travelling around the city a bit too fast for the pollution monitor to get all my data correctly. ;)