A replica Omega Seamaster Planet Ocean 600M is a copy of Omega's 600 meter dive watch, and the good ones look right on the wrist. Case profile, ceramic bezel insert, dial layout: none of that is hard to match. What separates a $120 watch from a $400 one is the movement, the crown threads, the crystal, and whether anyone bothered to align the bezel before shipping. Aim for the middle of the market and you get most of the look for a fraction of the price.
What the original does, so you know what to compare
The Planet Ocean launched in 2005 and has been Omega's deep diver ever since. Rated to 600 meters, it carries a helium escape valve at 10 o'clock, an arrow hand set, and a ceramic bezel insert that is often paired with Liquidmetal markings. Current Master Chronometer versions run calibers 8900, 8906, or the GMT 8906/8605 family, and they are anti-magnetic to 15,000 gauss. A replica will not replicate that last part. Nothing in the copy market has a silicon hairspring or a METAS certificate, so if magnetism resistance matters to you, this is not the watch.
Sizes, and which one to pick
The line has been sold in 39.5mm, 42mm, 43.5mm, and 45.5mm cases. Diameter gets all the attention, but lug to lug is what decides whether it sits well on a 6.5 inch wrist.
- 39.5mm: closest to a daily wearer. Good on wrists under 7 inches.
- 43.5mm: the classic Planet Ocean proportion, and the best-supported size in the copy market.
- 45.5mm: a genuine slab. It wears big and heavy, which is fine if that is what you want.
Movement tiers
This is where most of the price difference lives.
- Budget (under $150): cheap automatic or quartz, wrong beat rate, a rotor that spins like a coin, and a date that flips lazily.
- Mid ($250 to $400): Miyota 9015 or decorated Chinese automatics. The 9015 hacks and hand winds, which makes setting the watch feel normal.
- Top tier ($450 and up): clone 8500/8900 style movements running at 25,200 bph with a black balance wheel and engraved bridges that look close to the real decoration. GMT versions clone the 8605 and add a fourth hand.
What I check before paying
Photos hide a lot, so ask for specific angles.
- Bezel insert alignment at 12. If it is off by a hair in the listing photo, it will bother you forever.
- Crown threads and the helium valve crown. They should turn smoothly, not grind.
- Date window position and font. On the real watch the date sits close to the edge, and the numerals are slim.
- Anti-reflective coating. A blue or purple tint is normal. A washed-out milky look is not.
- Lume. Charge it with a phone light. Blue-green, even, and not patchy.
- End link fit at the lugs. Gaps are the fastest tell on a bracelet watch.
Water resistance: assume nothing
The 600m marking on the caseback is cosmetic on a replica. Seals, gaskets, and caseback torque are the parts most likely to be skipped. Treat it as splash resistant. If you want to swim, take it to a watchmaker and pay for a pressure test first, and accept that a failed test means you just bought a desk diver. Nobody warranties a copy.
What you give up
No warranty, no service network, no resale value worth mentioning, and no METAS-level accuracy. Sell it later and you will get a fraction of what you paid. Buy it because you like wearing it, not because it is an investment.