I'd appreciate that Projone. Someone else who were serious about their marketing of a quality bike was David Miall of Wisperbike. Together with his partner they'd created a highly successful company in another field which they then sold and moved into e-bikes. They didn't just import, but bought a major Chinese e-bike manufacturing company so have total control, but despite that they haven't found it an easy ride by any means.
When i say "parts bin", that's not intended to mean no good, merely that it's no different from what others are doing, and I'm quite sure your intended bike will be another of those. There aren't a huge number of manufacturers in China, just many companies marketing them as different bikes with name changes.
Lithium batteries are a big issue. Two stand out as being very good quality, the Panasonic 24 volt one at £306, and the BionX 36 volt at about £450. Clearly those wouldn't match your moderate price bike aim. Below that, two major suppliers have high powered bikes with 36 volt Li-ion batteries at about £250 and both with a history of failures, despite being manufactured by two of China's major battery manufacturers, one part of a very highly respected electronics company.
Bikes on ebay like the well established Scottish based Synergie brand have cheaper lithium batteries down to around £150. I don't know how well they've performed, but these tend to only be successful when coupled with relatively low powered motors.
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