Top pick: a mid-tier replica of the IW323775 running a Miyota 9015 inside a 316L stainless case, with a bezel that indexes cleanly at every marker and applied indices that sit flush to the dial. That combination wins because the money goes into the parts you handle every day, the winding feel, the bezel click, the dial depth, rather than into a box and a certificate. The criteria below are the ones that separate a watch you keep from one you resell within a month: movement, case and bezel execution, dial and lume, bracelet and clasp, water resistance, and the honesty of the seller about what is and is not included.

Movement: the single biggest fork in the road

The IW323775 reference belongs to IWC's three-hand dive family, and the genuine watch is a slim automatic. Replica makers solve that with three broad approaches: a cheap 21-jewel clone, a Miyota 9015, or a thin Swiss-architecture copy such as a Sellita SW300 pattern. The movement determines thickness, rotor noise, service life and whether the seconds hand sweeps or stutters.

  • Pros of a Miyota 9015 build: thin profile close to the original, smooth sweep, widely serviceable, parts are easy to source, good accuracy out of the box.
  • Cons: rotor can be audible in a quiet room, and the date change is instant rather than gradual, which a sharp-eyed owner will notice.
  • Pros of a Swiss-pattern automatic: closest feel to the genuine, quieter winding, better finishing visible through a display back.
  • Cons: higher price, harder to service locally, and quality varies a lot between batches.

Recommendation: choose the Miyota build unless you specifically want a display-back watch and are paying for the finishing that justifies it.

Case, bezel and crown

Ask for a straight-on macro shot and a 45-degree shot. On a dive watch the bezel is where corners get cut: a printed or badly filled insert, sloppy alignment at 12, backplay when you rock it, or a ratchet that feels gritty rather than crisp. IWC has used both internal and external rotating bezel designs across the Aquatimer line, so confirm which one the reference you want actually uses before you compare photos.

  • Check: lugs should be symmetrical, brushing should run one direction, and the crown should screw down without a gritty last quarter turn.
  • Check: the bezel triangle should center on the 12 o'clock marker, not drift left or right.
  • Red flag: polished chamfers that look rounded or fuzzy in photos, which usually means machine polishing without a hand finish.

Dial, hands and lume

Dial quality shows up in three places: printing sharpness, the height of applied indices, and how the hands are finished. Genuine-level dials have indices that catch light on their bevels; cheap ones look flat and sit like stickers. Lume is the fastest test you can run at home. Charge it under a lamp for 30 seconds and see how bright it goes and how long it lasts.

  • Pros of a good dial: correct font weight on the date wheel, crisp rehaut engraving, hands that line up exactly at 12.
  • Cons to accept: even strong replicas often have slightly warmer lume color than the original, and date wheel fonts are rarely exact.

Bracelet, strap and clasp

Solid end links that fit the lugs without gaps, screws rather than push pins, and a clasp that snaps with a firm click are the marks of a serious build. If the reference ships on a rubber strap, check that the strap is soft and that the buckle tang is thick enough not to bend. IWC's quick-change lug systems are frequently simplified on replicas, so ask directly whether the strap change works the same way as the original.

Water resistance: assume nothing

Very few replica watches are pressure tested, and a dive watch that fogs up is a ruined watch. Treat any water resistance claim as marketing until a local watchmaker has tested it, and never swim with a replica straight out of the box. If you need a watch for actual water use, buy a purpose-built diver instead.

Price tiers and what they buy

  1. Entry tier: correct silhouette, printed dial details, basic automatic. Fine for occasional wear, not for close inspection.
  2. Mid tier: the sweet spot. Better case finishing, Miyota movement, sharp dial, solid bracelet.
  3. Top tier: thin Swiss-pattern movement, hand-finished case, near-correct dial and lume. Worth it only if you handle the watch daily and care about the back of the case.

Questions to ask before you pay

  • Which exact movement is inside, and can you send a photo of the rotor?
  • Is the case 316L or 304 stainless?
  • Are the end links solid, and are the bracelet pins screwed?
  • Has the watch been water tested, and what is your return policy if it fogs?
  • Are the photos of the actual unit or a stock image?

Which buyer should pick which

If you want a daily-wear dive watch that looks right on the wrist and you are not chasing macro-detail accuracy, take the mid-tier Miyota build and put the savings into a proper service and pressure test. If you collect and compare details against the genuine, pay for the top tier and insist on real photos of the specific unit. If you only wear it a few times a month, the entry tier is enough, but budget for a replacement strap because that is usually the first part to fail.