Comparing this machine with the standard Neptune 4 is an unusually clean exercise, because on paper almost nothing differs. Same 225 mm plate, same 265 mm of height, same 300 °C hotend, same 110 °C bed, same direct-drive extruder, same bed-slinger layout. A specification table cannot tell these two printers apart.
That makes it a good page on which to be precise about what "Pro" is buying, because the honest answer is not what most product pages imply.
The wattage difference is inside the noise
The steady figures recorded here for the two machines differ by a small margin. That margin is not a measurement. Both numbers are class estimates derived from bed area, bed voltage and enclosure — and the difference between them is smaller than the uncertainty in either.
This is worth saying plainly because it is the kind of comparison that gets quoted. Do not choose between these two printers on power consumption. If someone tells you one is measurably cheaper to run than the other, ask what meter they used. A print-cost estimate for either should use the same figure and the same regional electricity rate, and the difference will be lost in the rounding either way.
What genuinely differs
Part cooling. The Pro's cooling arrangement is the substantive change, and it is the one that shows in parts. Better cooling means cleaner overhangs, sharper small features and more tolerance for printing PLA quickly. On a machine sold on speed, that matters more than it sounds — most speed-related quality loss on PLA is a cooling failure rather than a motion failure.
The plate surface. A PEI-coated spring steel sheet rather than a plain one changes the daily experience considerably: parts release when the plate cools instead of needing a scraper, and bed adhesion that is too strong stops being a way to gouge your build surface.
The extruder assembly. A dual-gear arrangement grips filament more securely, which matters most for flexibles and for anything that resists being pushed.
Which of those you will notice
If you print PLA display models with overhangs, the cooling is the reason to buy this one and it is a real reason.
If you print functional PETG and TPU parts, the extruder and the plate matter more than the cooling, and both are worth having.
If you print large, slow, simple geometry, you will struggle to tell the two apart, and the base model is the better purchase.
Living with a 225 mm bed-slinger
Everything true of the plainer model is true here: the plate is thin aluminium moving quickly on the Y axis, so mesh levelling wants doing at temperature and repeating after the machine is moved. Ringing is answered with the resonance calibration rather than with a slower profile. Tall narrow parts belong near the centre of the plate.
The hardened-nozzle point applies too. Stock is brass, and one spool of carbon-filled anything is enough to widen it — the 0.4 mm nozzle reference explains why a worn orifice is worse than a wrong one, because it drifts rather than fails.
Materials, and the constraint that is not the hotend
A 300 °C ceiling is generous, and it is not what limits this printer. The open frame is. ABS, ASA, unfilled nylon and polycarbonate are all held back by the surrounding air rather than by the nozzle's ceiling, and there is no enclosure here at any price.
Where the ceiling does earn its keep is filled PETG and filled PLA, which print a little hotter than their plain versions and do not care at all about ambient temperature. If your interest is stiff functional parts rather than heat resistance, that combination — carbon-filled PETG on an open direct-drive machine with good cooling — is one of the better value propositions in desktop printing, and it is exactly what this printer is set up for.
When the plain model is the better buy
Choosing on price alone points at the base model, because everything above is a refinement rather than a capability. Needing an enclosure points away from both. And printing near the plate limits is a reason to size up now — the Max version of this family exists precisely because 225 mm runs out sooner than people expect.