The first one is a legit Soco battery. It's an official Soco dealer in China. The second is the aftermarket ones. I've been told, without the correct BMS, you won't be able to display the correct battery level on your speedometer. 

Before ordering through here for something like a battery, check out the suppliers that will ship something 10kg, the size should be easy to estimate as well, that they will ship it. There are logistics providers who mention that they prohibit the shipment of batteries (depends where you are as well. Could be different there). If in any doubt, SuperBuy customer service was always pretty good at answering questions back. 

For the second one you found, I've seen several people get aftermarket batteries without an issue. Other people, like myself, build their own packs. The issue with these can be that the cells themselves may have a shorter lifespan and whether people trust the quality of soldering and connections inside if you have a bumpy ride. But then again, the OG soco battery wasn't any better with that, considering you can find tons of people having error codes and battery connection issues due to the BMS/poor soldering. If you go for the second option, you may find something similar on Alibaba, LightInTheBox, etc. (often bigger selection, cheaper than Aliexpress, but more legwork searching) that would be easier to ship over (if you have the battery shipping issue) and will still be a massive price cut off the OEM. On these sites, just check to make sure its a reputable seller. 

Thanks for that response, it gave me some context. My preferred battery would still be a DIY one with 21700 cells so I can gain some space, but I have absolutely no experience in building my own and I still haven't found someone to do custom build and buy it off of them yet so maybe I will get one of these from superbuy or alibaba instead 🙁