Also, in addition to these Amazon reviewer concerns, I could really use help understanding the difference to a first time user (besides almost $100) in buying from amazon

https://www.amazon.com/TENLOG-TL-D3-...9878047&sr=8-1

for $639

vs buying


https://www.amazon.com/New-Extruder-...9878047&sr=8-2

for $545 also on Amazon

Both seem to have the same essential feature and model names. but clearly they are not identical.