The information overload certainly takes its toll. I fall into analysis paralysis from time to time.Half my brain have same conclusions then you have......the other is pro Pylontech....man...it's hard...?
Can I ask which means of payment did you used with Basen... Paypal, wire...? I'm not sure what is best, PayPal protection or Alibaba trade insurance...
I do some weighing of the pros and cons and decide what is more important to me. You also have to decide whether the claims are true. 6000 cycles with 1 cycle per day is 16+ years. I'm wondering if their test used some super low 20% DoD as a cycle. There number of cycles is spec'd at so many different numbers, but if you read about the chemistry and not rely on the sales information, you will get more reliable information.
I have used a credit card and a debit card to purchase on AliExpress and Alibaba. Basen was the first to charge the 2.95% service charge, but also the first time I spent more than $500.