The top pick for most readers is a high-end custom Saxonia build with a hand-engraved balance cock and a correctly finished three-quarter plate, because the caseback is the one place where cheap fakes collapse under a loupe. I ranked every option below on four criteria: movement architecture visible through the display back, case metal and finishing, dial and outsize-date execution, and documentation that can survive a service check. Boxes, papers, and dealer stories are noise until those four line up.

Option 1: Budget Saxonia-style quartz and low-grade automatics

This is the tier sold on marketplaces and street stalls at fashion-watch money. The case is usually plated brass or low-grade steel, the crystal is mineral glass, and the dial printing is done in one pass, so the serif on "A. LANGE & SÖHNE" thickens and the "GLASHÜTTE I/SA" line sits too close to the center. Some use quartz, which you can rule out instantly: a Saxonia is a mechanical watch, full stop.

• Pros: cheap enough to treat as a disposable costume piece; easy to spot, so you will not be fooled about what you own.
• Cons: wrong metal, wrong crystal, wrong movement, and a caseback that is either closed or fitted with a printed rotor pretending to be a three-quarter plate; date windows are usually a single disc with sloppy alignment.

Buy it if: you want a stand-in for a photo or a costume and have no expectation of it passing a close look. Skip it if: anyone will ever turn the watch over.

Option 2: Mid-tier Asian automatic Saxonia replicas

These run a generic Asian automatic under a decorated plate or an open caseback with a stamped and painted movement. The proportions are closer to the real family, which spans roughly 35 mm to 40 mm depending on reference, and the dials often get the lancet hands and applied markers right at arm's length. The failure is depth: real Lange finishing has grained surfaces, polished bevels, gold chatons, and blued screws, and stamped decoration reads flat and shiny under a loupe.

• Pros: plausible size and wrist presence; sapphire crystal is common; the dial layout usually matches one actual reference rather than mashing two together.
• Cons: stamped rather than engraved balance cock; no true three-quarter plate geometry; outsize date wheels that jump unevenly or show a visible gap between the two discs; caseback engraving that is laser-etched rather than cut deep.

Buy it if: you want the silhouette and accept that the back is a giveaway. Skip it if: the seller claims the watch is genuine or "Swiss made."

Option 3: High-end custom Saxonia builds

This is where the money goes and where the detail work shows. The good builds use a solid gold or properly thick steel case, a hand-engraved balance cock over a plated movement, chatons with real screws, and a two-disc outsize date that snaps cleanly. The engraving is the tell: hand-cut work has varying depth and a slight wobble, while machine engraving is uniform to the point of looking printed.

• Pros: correct case metal and weight; dial typography that survives a loupe; date mechanism that behaves like a jumping two-disc system rather than a single printed wheel; hands in the right shape and finish.
• Cons: cost approaches or passes what a serviced entry-level piece from an established brand would run; the movement is still a clone, so service and parts are a real question; resale value is close to zero.

Buy it if: you want the closest visual match to a Saxonia Thin or Saxonia Automatic and you are keeping it. Skip it if: you are buying as an investment or plan to sell later.

The four checks that settle a sale

1. Caseback and movement. Ask for a sharp, straight-on photo of the display back with the balance cock in frame. Engraved beats stamped every time, and a closed caseback on a reference that should have a sapphire back is a hard no.
2. Outsize date. Not every Saxonia has one, so match the dial to the reference first. On models that do, confirm two separate date discs and a clean simultaneous jump. A single disc or a crooked window ends the conversation.
3. Dial text and hands. Check kerning on the brand name, the position of the city line, and whether the hands are the right shape for that reference. Sellers often combine the dial of one model with the case of another.
4. Metal, weight, and paperwork. Solid gold has a density plated brass cannot fake. Cross-check any serial against the brand's own published reference data, and treat a price that sits far below the going rate for a solid gold watch as the loudest tell of all.

Who should buy which

For a first purchase, go with the high-end build or nothing. Mid-tier replicas look fine in photos and disappointing in hand, and the budget tier exists mainly to be resold to someone who does not know what a Saxonia is. If your goal is a real Glashütte watch you can service and hand down, save instead: a replica movement has no parts network behind it, and counterfeit goods can be seized in transit, which leaves you with no recourse. Buy the tier that matches how often the watch will leave your wrist and be examined, and be honest with yourself about that number.