Let's just get this out of the way and say that looks matter. Love at first sight? Better looking over time? If you have zero interest in a certain electric bike's appearance, then trying to force a relationship will only make you unhappy in the end.
You arrive at the store and meet your bike. Take a good look at the style of the frame, the battery placement, as well as the color, and decide if you would like to get to know it better. White e-bike? Black e-bike? Or maybe you have your eye on that nice looking yellow e-bike. Make a decision.
It's What's Inside That Counts
So, you've decided to give a certain e-bike a chance. Now you've got to get it know it better. What's beneath that beautiful exterior?
Always make sure your e-bike has numbers listed for both volts and amp-hour. The higher the voltage the more power you have, the higher top speed you can hit, and the more likely you are to make it up a big hill.
The higher the listed number of amp-hours, the better range it will get. Consider amp-hours the size of the gas tank. What kind of range are you expecting? If you want to be able to travel 25 + miles on a single charge, then guess what? Size matters. Without a listed number of volts and amp-hours, it's all talk. That is the only way to truly know what your electric bike is capable of.
The Check Arrives
Now you've gotten to know your electric bike, and you're falling hard. Before you know it, the check arrives and it:
1) Doesn't affect you at all because it was what you were expecting
2) Cheaper than you expected so you buy an extra something
3) Far costlier than you could have imagined and you imagine yourself pinching pennies for the next few months.
Lesson learned: make sure you have a good idea of your budget for electric bikes and compare prices between different sellers. Always make sure to get the number of volts and amp-hours to compare.
A Few Other Points of Consideration
How is it powered?
Most electric bikes have some combination of manual pedaling, pedal assist (pedelec), and electric only (throttle) modes. Make sure you get the right one. If you have bad knees or just don't want to pedal, then make sure your electric bike can propel itself forward with just the throttle.
Who makes the battery?
Make sure your battery comes from a reputable manufacturer. Most major electric bike manufacturers use brand name batteries so you would literally be scraping the bottom of the barrel if you found one that didn't. Brand name batteries also tend to have much longer lives (charge cycles) due to more stringent testing.
How much weight can the e-bike support?
Electric bikes are built in a similar fashion to their non-electric counterparts. As such, their weight limits are roughly the same as well. Most e-bikes can support someone who is 300 lbs. Just because they can though, doesn't mean they should. Manufacturers typically post max weight limits 50 lbs. lower than their actual max to ensure reliability. A heavier rider would wear down the e-bike much faster and could potentially damage the spokes on the wheels.
Are there any user reviews, videos, or evidence that show the bike performing in a real-world setting?
Sometimes, the numbers don't match up with real world performance. Check to see if there are any reviews, videos, or other evidence that support the claims made. If the electric bikes you're looking for are available at a location nearby, go and test it out.
Always make sure the volts and amp-hour are listed and never buy an electric bike that does not have these numbers listed. They give you a general idea of what the real-world range can be.
Remember to focus on the main differentiators: looks, power, range, price, motor type (pedal, pedal assist, full electric), max supported weight, battery brand, and real world results.
Good luck with your e-bike hunt!