Presets vs Filament recommendations  

This has happened before, double-check the preset names

Be sure to differentiate between Prusament and Prusa supplied filament. For years, Prusa shipped, and so far as I know, continues to ship a spool of Prusa-labeled filament in the box that is manufactured by Filament PM. Prusament is their in-house brand. They are different. System filament presets are included for both. I just checked my Prusament PETG preset and it prints with 240C at layer 1 and 250C for other layers. The Prusa PETG preset prints at 230C at layer 1 and 240C for other layers.

RE: Presets vs Filament recommendations

bobstro gave correct answer.

Still, on my Mini, Prusament JetBlack PETG prints perfectly fine at 240C (slightly less stringing than at 250). So I use 230C for first layer (same temp as for first layer calibration), and 240C for the rest.
But as we know, "best" temperature depends on many things (nozzle size, print speed, etc.).. and so, maybe I get good results at 240C because I'm using Bondtech heatbreak.

RE: Presets vs Filament recommendations

I mean the setting in the printer interface, not the slicer. There is only one entry for PETG and it's PET 230/85. Doing first layer calibrations and preheating is a PITA because I frequently have to manually change  the temp to 250*. This is Prusa Galaxy Black. It says Prusament on the product page you get by scanning the QR code: https://prusament.com/spool/1a0d7b01/

I don't know... I found that over the last few years any decent quality filament has come to perform very consistently over quite a wide temperature range, so I have given up doing temperature towers unless there's something weird going on (now this is not to imply that you can't see some improvements in areas such as stringing etc by changing temps). So I've not seen any issues doing first layer calibration or preheating for any PETG with the printer's default of 230. I don't use the built-in first layer calibration method--and no one should--, I use the LiveZ MyWay calibration square instead, but I just use one gcode sliced for Generic PETG for any brand.

TL;DR I guess is, in my hands I haven't seen the need to manually adjust the temp for Prusament. 

Also if you want some customised preheat/levelling routines then just create some gcode files and load them to the printer.  You can then run them instead of selecting the preheat from the menu.  That way you can set whatever temps you want for both extruder and/or bed.

That's basically what people do when they use the LiveZ levelling method by Fuchsr.  I have several utility gcode files in the root of my sd card and all my normal print files are in sub folders.  I pretty much only use the Print from menu option now for most things.