The top pick is the top-tier fake IW371704 build with a decorated 7750-based chronograph movement, because it is the only tier that gets the 40.9 mm case proportion, the subdial spacing and the date window position close to the original. I compared the field on four points: dial printing and subdial placement, case and lug finishing, movement thickness and pusher feel, and caseback engraving plus strap quality. The genuine reference matters here, since the IW371704 is a 40.9 mm steel Portugieser Chronograph with a silver-tone dial, running seconds at 6, a 30-minute counter at 12 and a date at 3, so every replica is judged against a very specific layout.
Top pick: high-tier IW371704 replica
This is the build that starts from a correctly sized case and a properly spaced tri-compax layout. Because the genuine watch uses a Valjoux 7750 base, a replica on the same architecture can, in principle, match the subdial geometry and the 28,800 vph sweep instead of faking it with a thin quartz or a small modular movement.
Fake IWC IW371704: Real vs Replica Guide
- Pros: correct 40.9 mm case width, subdials at 12, 6 and 9 in the right proportion, sharp applied numerals and feuille hands, crisp "IWC Schaffhausen" printing, engraved rather than printed caseback text, tight pusher action.
- Cons: highest cost of the three tiers, thickness often lands at 12.8 to 13.5 mm against the original's roughly 12.3 mm, and the rotor can be audible on a quiet room.
- Use case: buyers who wear the watch with short sleeves, handle it in person, and care that the date font and the minutes track look right at arm's length.
Mid-tier IW371704 replica
The middle tier usually copies the outer case well but cuts corners on the parts you touch and read. It is the tier where the silhouette still works in photos and the flaws appear in hand.
- Pros: close case profile and lug curve, good enough dial color match, working chronograph, comfortable price for a daily wearer.
- Cons: date wheel font too wide or misaligned in the window, subdial rings with flat printing, softer polishing on the bezel edge, thinner strap leather, inconsistent engraving depth on the caseback.
- Use case: someone who wants the Portugieser look for occasional wear and accepts a date window that reads slightly off under close inspection.
Budget IW371704 replica
The entry level is where the reference gets lost. Expect the right general idea and the wrong details, and buy it only if the price reflects that.
- Pros: lowest cost, immediate availability, acceptable from two meters away, chronograph function usually present.
- Cons: case too thick or too wide, hands that look stamped rather than finished, lume that does not match, weak water sealing, crown that feels loose, strap that stiffens after a month.
- Use case: a first replica to test whether the 40.9 mm Portugieser size suits your wrist before spending on the top tier.
Fake versus genuine: the honest gap
No replica matches the original in finishing under a loupe or in long-term serviceability. The genuine caliber is regulated and supported; a replica movement is not. Water resistance on any fake is a guess, so keep it away from showers and pools regardless of what the listing says. What the top tier does deliver is the correct proportions and a dial that reads correctly across a table.
Checks before you commit
- Ask for a straight-on dial photo and a side profile photo, then measure thickness against the reference.
- Confirm the date sits centered at 3 and the font weight matches the original print.
- Look at the gap between the subdial rings and the applied numerals; uneven spacing is the fastest tell.
- Ask whether the caseback text is engraved or laser printed.
- Request a short video with the chronograph running to hear the pusher click and the rotor.