FDM printers are AWFUL at small parts. they can not print to close tolerances when those tolerances are tight.
For prints larger than will fit in a Form 2, their course printing quality is more acceptable… but it is not unusual in small items for parts to be a full mm or more off dimension.
Also- the “strength” of their parts is over rated. Delamination - especially in the harder to print materials like ABS is a problem and perhaps their worst failing is their relatively low range of stable temperatures. Materials like PLA can not even stand ordinary sunlight on a warm day without warping and halving their strength.
Meanwhile- Form2’ s Rigid, Tough and Durable resins all compare pretty well to the best FDM can offer… but with far finer tolerances and surface finishes. Durable is a decent analog for nylon. Not quite as bullet proof but certainly usable for parts that will suffer mild abrasions or deflections.
what it comes down to is what you need from the printer.
for robotics applications, FDM DOES allow you to print in ABS and Nylon- albeit with less strength than properly injected or milled parts in those materials.
if you need to make larger structural members as well as small parts and can only afford one printer- then you might want to go with FDM- but a good quality printer capable of handling ABS and Nylon is gonna run you pretty close to what the Form2 costs.
It must have a full enclosure to achieve the temperature control required to print ABS and Nylon.
And- if you are going that route- you should opt for a machine with a dual extruder system- for 3 reasons… one- its not hard to design something that will take more than 1 kg of filament- and a dual extruder machine will enable you to pick up where the last spool left off with the second extruder- automatically. Second, because one of the biggest wastes in filament printing is how many partial rolls of filament that you end up with, that you can’t be sure have enough on them for the print you need to run… dual extruders allow you to put two partial rolls of the same filament on to make better use of each roll.
And third and most importantly- a dual extruder machine enables you to run DISSOLVABLE filament- so that you can print support structures that can be washed away- and makes possible higher quality and more complex prints.
( it can also print in different colors- but that is useless imho.- altho- it might be useful to be able to mix different filaments, such as ABS and flexible, to achieve hybrid properties. )
If you go for dual extruder- make sure its a machine that can Retract the extruder that is NOT in use- to prevent problems with the second nozzle striking the print.
I think Ulitmaker makes one- and the NEWER Raise 3D is also very well reviewed.