Hi! I don’t know if this is still relevant to you. I just want to share my experience with you, maybe it will help someone to choose a fit 3D printer…
I just bought an A6 and so far am quite pleased with it. Looking at the photos of the A8, it looks like the A6 has a sturdier frame. If you want to see all the differences just look at the spec sheets for the two on AliExpress or Ebay. The A6 is a little larger than a standard i3, about 220mm x 220mm x 240mm.
It took about 5 hours to build the A6 following the tutorial on Youtube. So far I have been using it with Cura (the slicer software) and I have done about 10 prints – it’s my first printer so I can’t make any comparisons, but it appears to be solid and well specked.
I’m still in the experimental stage, but I have made one small modification. The Y-axis idle pulley was not turning, so I put small washers either side of the supports so that it can turn without touching the sides.
If you want to know more about how to choose the 3d printer and make the right decision, I will recommend reading this article.
https://top3dshop.com/blog/3d-printer-buying-guide
It was very helpful to me.
Good luck with your choice!