I have a bit more advanced question regarding PETG. I believe that this can be tuned in, but there are just too many settings-combinations so it would take me a long time to hit the perfect one.
I use Overture PETG. It seems that I will be able to tune in perfect params for everything but bridges sooner or later. The bridges can look okay - if you don’t look under the bridge. Layer adhesion in bridge is the problem I have. Let me show you some pictures. Here is classic temp tower turned around:
As you can see, first horizontal layer are just strings, which I can pull around and eventually even tear. This is not so much of a visual problem for me, but structural. When it comes to printing real parts, then the problem is obvious:
But with certain settings, this can be improved a lot:
The last pic is of config I randomly put together, but unfortunately do not have it anymore 
- it was not perfect and therefore I did not save it.
After googling around, I figured that following settings affect bridges:
- temp
- cooling
- bridge speed
But the trick is that bridge speed can be optimal in lower range of around 20 or higher range in around 80. When it comes to temp - some say print with lower temps of around 230. Some say print with 270-280. Then there is question of cooling. Should it be high or low? Should it be high when temps are high or… You see my point? Just way too many combinations to play with.
Is here anyone of people who claim that PETG prints just fine and when you print temp tower and turn it around - it has good first layers of bridge? Like I said, I am not so much interested in visual appearance - it is clear that it is possible to make it look good on the outside. And I believe here is where majority of differences come into - it is hard to test all possibilities of all different models that can be printed and some people do not print parts that have complicated bridges and overhangs - printing is easy then, not much to tune into.