Prusa Slicer and Ender 3 Pro

[curious aardvark]

Also the ender 3 is significantly slower than any actual prusa design. So prusa slicer is probably slowing down certain sections to give you better prints - that cura might not be doing.
Go with prusa :-)

Also that's a ridiculous amount of time for a pencil holder - got a link to the stl or thingiverse page ?

Check your number of shells and infill settings.

An awful lot of 'standard' setting use incredibly dense infill - totally unnecassary.

Drop the link and I'll run it through simplify3d and see what kind of times trhat gives me.

Also and this doesn't really make sense, but is how it works - the larger the print the less dense you can make the infill while still getting the same size mesh that a higher infill generates with smaller models.

It's never made sense to me - but it's something to do with how slicers calculate things.

ALWAYS generate a preview of your models and run through the print virtually before accepting settings.

My standard infill settings are: tringular patterna nd 15%
For large models I can often go down to 10% and for small ones frequently up to 25-35%

Depends on what it's being used for and what the top surface looks like.

Also while waiting - go watch a lot of videos on how to make ender 3's work and how to fix all the problems they have.

Unfortunately you've already ordered it so i can't tell you to buy something else.

But they've been around a while and there are probably several thousand youtube videos on how to fix each individual issue that might crop up.
Good luck :-)

And have a chat with Xayoz, they'll put you straight on how to get the best from the ender and probably save a lot of time and swearing :-)