Short answer
A replica IW371459 gets the silhouette right and the dial close. The tells sit in the case thickness, the chronograph actuation and the fine print on the dial. If you want a watch that reads as a Portugieser Chronograph across a table, the top tier gets you there. If you want one that survives a caliper and a loupe, no replica of this reference clears that bar.
What the genuine watch is
The reference belongs to IWC's Portugieser Chronograph line, the 3714 family, a series that ran for years before IWC moved the model to its in-house 69355 caliber.
- Stainless steel case, about 40.9mm across, close to 12.3mm thick
- Two register dial: chronograph minutes at 12, running seconds at 6
- Feuille hands, applied Arabic numerals, railroad minute track, no date window
- Caliber 79350, a Valjoux 7750 base reworked by IWC, 28,800 vph, around 44 hours of reserve
- Solid caseback, 30m water resistance, alligator strap
References in this family differ in dial color, hand color and strap. That matters at order time. Match the replica to photos of the exact reference, not to a listing that happens to show a silver dial because that is what the seller had in stock.
What good replicas get right
Case shape comes first, and the better factories have the lugs and polished bezel down to a believable curve. Dial layout is the next win: two subdials in the right places, the railroad track printing, applied numerals at 12 and 6 catching light the way they should. Crown and pushers sit at the right height.
Finishing on the mid and top tiers is solid. Brushed flanks, polished bezel, crisp bevels on the lugs. Under a shirt cuff it passes.
Where replicas give themselves away
- Thickness. The 7750 base inside most replicas is deeper than the 79350, so cases run 1mm to 2mm fat. Lay a replica next to the real thing on a flat surface and you see it.
- Crown positions. The 7750 carries a date mechanism. If the crown has a middle position that clicks for a date the dial does not have, that is a problem you cannot explain away.
- Chrono start. On a cam and pinion setup the chronograph seconds hand can twitch when you push the start button. The real thing sweeps from zero.
- Dial print. Subdial rings, the branding at 12, the text above the small seconds, the engraving on the back. Cheap reps smear these.
- Hands. Feuille hands are leaf shaped and the curve is hard to fake. Flat or blunt hands show up fast.
Pre-purchase checklist
- Compare listing photos to catalog shots of the reference, dial color and hand color included.
- Ask for a photo of the watch on a caliper. Past 13.5mm on this case, you are accepting a compromise.
- Ask what movement is inside. A7750, a modified A7750 with the 12 and 6 layout, or quartz. Quartz is a no for this reference.
- Request a video of the chronograph starting and stopping. Watch the seconds hand at the moment of the push.
- Pull the crown and count the positions.
- Confirm strap and buckle type in writing.
- Ask about water resistance, then ignore the answer. Treat it as splash proof at best.
Movement and servicing notes
The 7750 clones are workhorses. They run, any competent watchmaker can service them, and parts are common. That is the one genuine advantage of the replica route. Budget for a service if the watch arrives running fast or the chrono refuses to reset to zero. Someone who works on Chinese 7750s will handle it in an afternoon.
Keep it away from water, keep it off a magnetic charging pad, and do not treat the pushers like a poolside stopwatch. That covers most failure modes.
Price and expectations
Cheap versions of this reference look the part in a web photo and disappoint in hand. The money goes into case profile, dial print and movement finishing. Anyone promising a replica that is indistinguishable from the real thing is selling a story. A good replica is a good watch in its own right, and that is the honest bar to hold it to.