A few months ago I ordered Prusament PETG off of Amazon. I was curious about how well it would work considering Prusa seem to have their act together regarding all things 3D printing. The increased accuracy of this filament was hard to ignore. I ordered this off of Amazon knowing there would be months (at the time) to wait for it to be in stock. I did not order directly from Prusa because shipping came out to about the same total, and I would not need to sign for the shipment sent from Amazon.
My experience with PETG has been generally positive, and I have sourced a few types from United States manufacturers in an attempt to avoid higher shipping costs. I did end up going with Sunlu PETG on Amazon, but the Non-Black blue I tried did have issues with color consistency.
I think PETG is a wonderful material due to its mechanical properties and its higher melting point compared to PLA, but the PETG I have used seem to have an inverse relation to quality versus layer adhesion at decent print speeds. Increasing the part fan speed causes warping on larger parts as well. The general solution I have found up until now has been to slow down the prints as well as the parts fan speed.
This seems to not be an issue nearly as much with Prusament PETG. I also had to dial back my retraction distance and speed to get good quality, but I am thoroughly impressed. The layer adhesion printing near the upper range of the suggested temp seems to be strong. I have my extruder temp set to 260 C, my bed set to 80 C and the ambient air temp of my enclosure set to 32 C. Its also apparent to me that the photos I have taken do not do this filament justice. Its generally shiny and gorgeous to look at with its reflective particles.
I have yet to print larger parts, but I plan on this being the primary filament on the CNC project. I will likely use up most of the 3kg I bought for that purpose and large parts will be involved. I will likely buy more of this in the future, but the only downside I can think of is extra cost associated with shipping and the longer lead times currently.