personally I would say if you can afford an ultimaker - get an ultimaker.

It's not really a non-standard filament size as it's the larger of the two standard sizes. I've not seen any filament that doesn't come in both sizes so that's not an issue.
It says 2.85mm but 3mm should work just as long as you tell the slicing software. And pretty much all filament comes in either 2.85 or 3mm.

The flash forge pro is a good machine.
But:
Ultimaker has larger print volume.
Ultimaker has much higher placement precision.
Ultimaker is much faster.
Ultimaker uses standard gcode - so you can use pretty much any slicer you like - flashforge uses x3g files, which can cause issues with some slicers.

Basically there is a reason ultimakers keep consistently winning awards.

If dual printheads are important to you - you can upgrade the ultimaker to a dual extruder quite easily - the place for the second extruder is already on the carriage.

The only reason for getting a fully enclosed machine like the ffcp is to print abs. And you don't need to ever use abs if you don't want to. lots of alternatives.


get the ultimaker :-)