Hey RG,
Do your research, find your bike, make your purchase from a reliable supplier and don't look back... But, don't just do research for the bike and price, research the bike's company and the companies principles. Pick a bike from a company that has been around awhile, 3 to 5 years maybe. The e-bike world is littered with companies that have crashed and burned.
Is the company supportive of it's products, customers and dealers? Do they support their earlier models with ALL parts, including batteries and electronics? Batteries will change, for the better. When you have used up your battery, can you get a new battery for that proprietary setup on your bike? There are great idea people in the e-bike world and they can put out an awesome bike that works great and gets great reviews but is it a one off? Can you shop at Amazon or ebay for parts and accessories? If you need a new handle bar because you found that the bar you got with the bike doesn't have enough rise to ride comfortably? Cogs, chainrings, freewheel, spokes, bearings, seat and post, fenders and so much more, you get the idea. Can you get these through your dealer? Can your dealer get these parts from the manufacture?
Don't stress over these things! It's just that this industry is still so new there will be failures. Not so much that the one new bike that so and so company just introduced was a failure, after all it has gotten great reviews! But will that bike and company be around next year? Edsel was Henry Ford's son and it failed.
Find your bike, pull the trigger and get it! Enjoy!!!
Good luck - JR