Count the rolls you need ready together, not every roll you own. A shelf of ten colors does not automatically require a four-spool dryer.
One printer, one material at a time
The S2 handles one standard spool. It can be the simpler fit if you finish one drying cycle before changing materials. Oversized rolls need their actual dimensions checked; “1 kg” does not describe one universal spool shape.
Two colors or a support material
The Space Pi Plus holds two rolls in one environment. It suits pairs that can share drying settings. If you mostly print one color, make sure the second slot will earn its space on your bench.
Four spools with a shared requirement
The S4 makes sense when multiple rolls need preparation within its 70°C range. Think in batches: how often would all four places be useful? Extra feed ports help routing, but do not establish separate heat control.
Two temperature zones
The X4 divides four spools across two independent chambers. That gives pairs their own settings, rather than one independently controlled temperature per spool. Choose it when that distinction changes your actual workflow.
Make the space check before buying
Allow room for opening the lid, inserting a spool, cables and the path to the printer. A machine that fits under a shelf when shut may be awkward to load. Check the current manufacturer’s dimensions and clearance information alongside your largest spool.
Use the material temperature guide to decide the heat class, then use the Amazon options below to check the exact version and accessories. Capacity is worth paying for when it removes repeated interruptions, not just because the larger machine is available.