Short answer first: the replica IW371701 worth your money is the one that gets the dial right. Two subdials, running seconds at 9 and the chronograph counter at 12, a date window at 3, a 40.9 mm steel case, and a working automatic chronograph under a sapphire display back. Miss any of those and you are buying a costume, not a copy.
What the IW371701 actually is
The IW371701 is the stainless steel Portugieser Chronograph with a black dial. IWC sized the case at 40.9 mm across and roughly 12 mm thick, which is thin for an automatic chrono and the reason it slips under a cuff. The dial uses applied rhodium Arabic numerals, leaf-shaped hands, a fine minutes track, and a small date aperture at 3 o'clock. There is no subdial at 6. That single detail matters more than anything else in this guide.
Inside the real watch sits the IWC caliber 79320, a Valjoux 7750 that IWC reworked into a two-register layout. It beats at 28,800 vibrations per hour, holds about 44 hours of reserve, and shows through a sapphire caseback. Lugs are 20 mm, water resistance is 3 bar, and the strap is alligator.
The three tiers of replica you will find
Quartz lookalikes
Usually the right diameter in listing photos and wrong everywhere else. Faux subdials that never move, pushers with no travel, a case that feels hollow, and often a solid caseback to hide the nothing inside. Cheap, and it shows within a day of wearing.
Mid-tier automatic builds
These run a 7750 or a Chinese clone of it, so the chronograph works, the seconds sweep, and the pushers snap. The catch is the base layout. A stock 7750 carries a 12-hour counter at 6 o'clock, and the genuine Portugieser does not. Replica makers handle this in one of two ways: they leave that subdial off and disable the hand, or they fit a decorative plate over the movement. The first approach is cleaner, and it is the one I look for.
Top tier
Correct two-register dial, modified or well-decorated movement, applied indices with real bevels, domed sapphire with anti-reflective coating on both faces, a properly shaped crown, and a rotor engraved to resemble IWC finishing. You pay for the parts nobody sees until the watch is off your wrist.
What I check before anything else
- Subdial count. Two. One at 9, one at 12. A third at 6 is an instant no.
- Date aperture position and shape. At 3, cut clean, no cyclops, no white plastic ring showing.
- Dial printing. The minutes track should be fine and even, not a thick grey band.
- Hands. Leaf-shaped, polished, and long enough to reach the track. Short hands are the most common tell.
- Case depth. A replica that runs 2 mm too thick looks wrong in profile and sits badly on the wrist.
- Caseback. The genuine has sapphire. If the listing shows a solid steel back, ask why.
- Pusher feel. Start, stop, reset. Reset should snap back to zero without a wobble.
- Lug width. 20 mm. A 22 mm strap is a sign the case is oversized.
Movement, and why it decides the price
A genuine ETA 7750 inside a replica is a good sign, not a bad one. Any competent watchmaker can service it, parts exist, and it will hold time. A no-name clone can run well for years or die in months, and nobody will want to open it. If the seller cannot tell you which movement is inside, assume the worst. Ask too whether the chronograph is functional or decorative, because quartz replicas sometimes wire the pushers to nothing while the subdials spin on a battery-driven gear train.
What no replica gets right
Movement finishing under the display back is the honest answer. IWC's perlage, Geneva stripes, blued screws, and engraved bridges look a certain way under a loupe, and replicas get close at arm's length then fall apart at 5x magnification. Crystal coating is the second gap. Genuine IWC anti-reflective treatment has a faint blue tint and stays clear at angles. Cheap coating turns purple and washes the dial grey. Third is the strap. Most replicas ship with embossed leather that cracks inside a season, so budget for a replacement from day one.
Realistic expectations
A replica IW371701 is not an IWC. There is no warranty, resale is close to zero, and the legal situation depends on where you live and how the piece crosses a border. Water resistance is not tested, so keep it away from pools and showers no matter what the listing claims. Treat it as a look and a wearing experience. Buy from someone with real photos and a return policy, and decide in advance whether you want the watch to fool a stranger across a table or a friend holding it in hand. Those are two different purchases at two very different prices.