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Generally for these heavier duty direct drive brushless motors reviews seem very positive. For the lighter geared hub motors the reviews are more hit and miss and the weight rating is half. These direct drive motors are rated to 200kg load but the geared hub motors are rated to 100kg.
I'm not seeing much negativity about these direct drive motors in fact some reviews are positively glowing with how surprisingly good they are and they seem to be lasting a long time. The motors are fully sealed from the elements and don't require maintenance in contrast people with geared hubs have had to replace gears on occasion and they do have to break the seal to replace those gears which if they don't refresh the seal may lead to water ingress. From one review it states the wheel sold as 500W, 1000W and 1500W are the same wheel and its only the controller supplied that varies so surely that is a lot of over-engineering on the 500W and 1000W wheels if capable of taking up to 1500W but only run as 500W or 1000W.
One of the reviews sounds like he has bought his 5th wheel but is writing in a very positive tone so clearly has been very pleased with all the previous wheels. Sounds like he is converting lots of bikes for friends or family.
Having read a lot of material I think the direct drive hub motors are a better option than the geared hub motors from these very cheap suppliers. Yes you lose some efficiency but they just seem to work better thanks to their simplicity. Clearly the wheels are very heavy and you probably lose 20-30% of the range compared to using the same battery with a geared hub motor plus cycling with a discharged battery has more drag but overall seems a very good option for those who want a e-bike on a budget. Also a huge amount of low cost spares available from ebay and aliexpress if you do break the controller or wear out the throttle controller etc. Upgrade options too.