There are individuals who claim to have lost considerable amounts of weight by using an electric bike. A recent prospective cohort study however found that people using e-bikes have a higher BMI. By making the biking terrain less of an issue, people who wouldn't otherwise consider biking can use the electric assistance when needed and otherwise pedal as they are able. This means people of lower fitness levels or who haven't cycled in many years can start enjoying the many health benefits E-bikes have to offer. 
We ran the C330 almost entirely in its speediest Turbo setting, switching back to Eco or Tour in heavy traffic for a more predictable assistance weaving between cars. Crucially, the display also displays how much assistance you’re getting as well as your speed, trip distance, etc. We used this to ease-back effort and stay in a light power sweet-spot, arriving at WIRED’s HQ without breaking a sweat.
For many bikes, battery range is more important that total power (because they're all pretty powerful). You want a bike that delivers a range long enough for your rides at the power levels you want. Most e-bikes will have three to five levels of assist kicking in anywhere from 25 percent of you pedal power to 200 percent boost. Consider how fast the battery takes to recharge, especially if you'll be using your bike for long commutes.