Quick answer
A fake IW328098 v4 is a replica of the IWC Pilot's Watch reference IW328098, sold as the fourth revision of that replica run. The "v4" is a seller's version label, not an IWC code. It usually means the maker changed something after v3: dial print, date font, crown shape, case profile, or the movement inside. It is a batch marker, not a quality grade. Two sellers can both list a v4 and ship different watches.
What the version tag actually tracks
Replica makers release updates in sequence, and sellers add v1, v2, v3, v4 to keep track. A jump to v4 often follows feedback on the previous run, so you see corrections to things buyers complain about: the spacing of the dial text, the height of the applied numerals, the polish on the bezel edge, the lume color. Ask what changed between v3 and v4. A seller who cannot answer is guessing, and so are you.
Details I check on an IW328098 replica
- Case finishing. Brushed flanks should meet polished edges with a clean line. Soft, rounded transitions are the usual giveaway.
- Dial. Print crispness, the gap between the brand text and the model line, applied numeral height, and lume that sits level with the dial surface.
- Hands. Length, tip shape, and the height of the seconds pinion above the dial.
- Date window. Cutout shape, font weight, alignment in the aperture, and whether the frame matches the reference.
- Crown. Size, engraving depth, and how the threads engage when you wind and set.
- Caseback. Engraving depth, reference number format, and sapphire tint.
- Movement. Winding feel, rotor noise, power reserve, and beat rate (most run at 28,800 vph).
Why the numbering drifts
Parts supply changes more often than the outside of the watch does. A dial supplier shifts, a case set gets retooled, a movement batch changes, and the next run gets a new number. That is why a v4 from one source and a v3 from another can be nearly the same watch, while a v4 and a v2 rarely are.
How to judge a listing before you buy
Ask for a straight-on dial shot in daylight, a macro of the caseback, and a short video of the seconds hand sweeping. Look at the crown position, the lug holes, and the gap between the case and the end links. Confirm which version is shipping and what changed from the last one. If the listing only shows studio renders, treat the version tag as marketing until you see the actual watch.
What the tag cannot tell you
Water resistance, long-term reliability, and service options are not covered by a version number. Those depend on the specific case, gaskets, and movement in the watch you receive. Judge the sample, not the label.