Because the power is applied through the chain and sprocket, power is typically limited to around 250–500 watts to protect against fast wear on the drivetrain. An electric mid-drive combined with an internal gear hub at the back hub may require care due to the lack of a clutch mechanism to soften the shock to the gears at the moment of re-engagement. A continuously variable transmission or a fully automatic internal gear hub may reduce the shocks due to the viscosity of oils used for liquid coupling instead of the mechanical couplings of the conventional internal gear hubs.
I think this is a super interesting bike. I like seeing IZIP stepping into the world of Brose motors. Brose bikes always look clean and refined because of the battery integration. This bike is a pretty great value for what you get. Totally integrated lights, rear rack, fenders, and plus sized tires are all great to have. I wish it had a dual chainring in the front, but you can always add one on a Brose motor.
The Focus comes with lots of extras: front and rear lights, bell, fenders, chain guard and rack. The Panasonic drive system that powers it is the same unit that was on the Kalkhoff bike that climbed to the top of the Pikes Peak bicycle race, one of only 3 types of bikes to survive this 8000 foot 20-mile climb in 2012. The Panasonic drive system is a well built piece of E-bike engineering which drives the bottom bracket and powers the rear wheel through the same drive chain as the rider. It is only available on OEM bikes which have been-purpose built using it. It stands as one of the most refined mid-drive systems ever built.
Some power-on-demand only e-bikes can hardly be confused with, let alone categorised as, bicycles. For example, the Noped is a term used by the Ministry of Transportation of Ontario for e-bikes which do not have pedals or in which the pedals have been removed from their motorised bicycle. These are better categorised as electric mopeds or electric motorcycles.
Because e-bikes are capable of greater speeds for longer periods of time than standard bikes, you want extra control. Wider tires provide traction and some bump absorption with little penalty. You also want strong brakes to slow you (and all that extra weight) easily. It's worth looking at the quality of the brakes and investing in bikes with better ones if you can.