I have an Izip & a EG Oahu electric bikes. The Izip was $800, the EG $1650. They both have pedal assist which, when switched on, makes it feel like you always have a wind at your back. Both also have the option of throttle-only (think moped) or you can completely turn the motor off & pedal.
The Izip has a smaller battery (hence the cheaper price) but I can get up to 18-20 miles w/pedal asst. nice for buzzing around town or to the store or pub. The EG is the Cadillac of bikes. You can get up to 25 miles in the low pedal asst setting; 12-18 at the medium setting; 8-12 with no pedaling. It also can cruise up to 28-30 mph depending on rider weight. It's a powerful, fun machine!
My hubby & I will cruise to lunch or stop at a craft brewery & bring the charger & plug er in if we're far from home to assure we'll make it back without running out of battery on the EG. The Izip is easy to pedal by itself, but the EG is a slug due to its size & weight.
We really enjoy them & if I had to do it over, I'd buy myself the EG for the faster speeds & increased fun factor. We've been seeing more & more electric bikes on the roads lately. Schwinn makes them now too & someone said they bought their Izip at Walmart, of all places!