A snapshot dated 2026-09-06. Here is how it could be wrong.
The Bambu P2S Combo with its exhaust kit wins at 7.240 out of 10 while scoring 4.6 on openness, against 9.0 for the QIDI Q2 it displaced. Since January 2025 any slicer other than Bambu Studio must start prints through Bambu Connect, on a local network as well as in the cloud. There is no browser interface, no published application programming interface (API), and the firmware is closed.
Rob has said that "it just works" outweighs ideological purity for this purchase, and the ranking takes him at his word. The risk is that he is a homelab owner who designs in OpenSCAD, so this is the judgment most likely to read differently in a year than it does today. Push openness from 15 to 30 and the Q2 wins at 7.652, the widest margin any configuration achieves under any weighting in this study. That is not a knife-edge sensitivity; it is a different answer to a different person, and the tool has the slider.
The second weakness is the magazine, and it is honest to say it was scored twice. Bambu's Automatic Material System (AMS) 2 Pro sat at 4.5 on 2026-09-07 and sits at 7.0 now. Nothing about the box changed. What changed is that acrylonitrile butadiene styrene reinforced with glass fiber (ABS-GF) went from routine to occasional, so a filament the AMS refuses stopped being the filament Rob most wanted loaded.
Neither magazine in contention has a clean record, and neither fault is closed.
The AMS 2 Pro's feeder slots intermittently grind filament on first load and need a manual nudge (ki-bambu-ams-2-pro-feed-grinding, common and open on 2026-09-06). That is a fault in the recommendation, and it is the kind of friction Rob is buying a magazine to avoid.
Launch QIDI Boxes were worse: Tom's Hardware found the path "constantly jammed while attempting multicolor", and a second box QIDI sent behaved identically. Owners say a V2 revision fixed it, some at 450 to 792 hours without one, but no reviewer has re-tested it and Tom's Hardware still called the Box broken on 2026-08-12, having not been sent one. That its list accepts ABS filled with glass fiber (ABS-GF) is QIDI's own claim; nobody has published a long ABS-GF run through one. This now bears on the runner-up rather than the winner.
The first version of this report recommended the P2S. On 2026-09-07 Rob corrected two things: he wants a filament magazine rather than multi-color printing, and ABS-GF is in scope. That doubled the materials weight to 20 and moved the Q2 from sixth to first, because Bambu's AMS family refuses any filament containing carbon fiber (CF) or glass fiber (GF).
On 2026-09-08, asked the question this report had itself named as decisive, Rob said ABS-GF is occasional rather than routine. Materials came back to 15, the magazine weight that had been borrowed to fund it was returned, the AMS rows were re-scored from 4.5 to 7.0, and the P2S came back to first.
No fact about any machine changed on either date. Both moves were requirements corrections, and a reader should draw the obvious conclusion: take the weights, not the ranking. The top five sit within 0.28 of a point, the tool has sliders and six presets, and this report has now been wrong twice about what its own buyer wanted.
There is a sharper lesson in the second move. This report published a sensitivity claim that was not true. It said that dropping materials back toward 10 would reverse the ranking on its own. It would not have: tested before anything was re-scored, the Q2's lead widened to 7.160 against 6.860, because the exclusion was costing Bambu points in two judgments and returning the weight raised the second one. The recommendation changed only once the magazine judgment itself was re-scored. A stated sensitivity that nobody tests is a guess with a number on it.
Bambu's authorization change, in firmware from January 2025, routes any print started from a slicer other than Bambu Studio through Bambu Connect, on a local network as well as in the cloud. Developer Mode is the only escape, and Bambu called it unsupported in May 2026. The openness score of 4.6 describes policy, and policy is revocable. Prices move too. The P2S Combo's $749 is an everyday price, but the X2D Print More Bundle at rank seven rests on $1,149 struck from $1,258, and the Prusa MK4S with the Multi Material Unit (MMU3) fits at $1,230.38 only on a September 2026 promotion, against $1,442 at list.
Only 70 of the study's sources are independent measured tests. Four of 67 configurations stay capped on reliability, 33 on practicalities, for want of a noise measurement. On the shortlist, the Plus5 at rank five had three months in the field, the X2D at rank four under five, and the Snapmaker U1's noise is unmeasured.
Eleven of 180 dated issues carry a severity of "safety", and scope is everything. One is a real recall, now closed: the Bambu A1 heatbed cable, 2024-01-28, remediated in current stock. Two are common. A thermistor on the A1's board can overheat and melt nearby plastic; Bambu puts the rate near 0.052%, revised the board in 2025, but not the P1 series, which bears on the refurbished P1S. And the QIDI Plus4's chamber-heater relay was undersized for US 120-volt supply; QIDI capped the power and revised the board, and no recall followed. That is the Plus4, not the Q2, but it is the brand's record. The rest are isolated single reports: two Plus4 owners and a Creality K1 Max owner report fires, one losing a home. An anecdote is evidence of an anecdote.
Sixteen prices in the first pass were wrong, usually because a page's default variant is not the base product: the P2S Combo went in at $780, a different bundle, against $749. The first scoring pass was discarded outright: it capped 23 of 67 configurations on reliability and 44 on noise and put every Bambu P1S at 2.8, measuring our research coverage rather than the machines. A gathering pass added 165 sources and 85 known issues; the P1S rose to 8.0, the Q2 fell from roughly 7 to 4.0: movement both ways, the check that nothing was rescued.
One: openness matters more to Rob than he said. Raise it from 15 to 30 and the QIDI Q2 wins at 7.652. This is the likeliest of the three, because it turns on his own tolerance for Bambu Connect rather than on any new evidence, and nothing has to happen in the world for it to be true.
Two: ABS-GF turns out routine after all. Raise materials from 15 to 35 and the Bambu X2D wins at 7.325, not the P2S and not the Q2. This is the reverse of the correction made on 2026-09-08, and worth knowing because the answer under it is a third machine.
Three: the printer goes somewhere nobody sits. Drop the $19.99 exhaust kit and buy the bare P2S Combo at $795.81, second at 7.145. The recommendation degrades gracefully rather than changing.