Are GMT watches worth it?

If you check another zone daily, the Skyhawk removes the setting entirely: it synchronizes to radio time signals across 43 cities, holds dual time and a perpetual calendar, and runs on light behind anti-reflective sapphire.

It is a 45mm module rather than a movement, so its life ends when Citizen stops supporting the U680. For someone whose work runs on two time zones, that is a trade worth making.

It sets itself by radio, runs on light and is rated to 200m behind sapphire — and it is a module, not a movement. When the module stops being made, the watch is finished, however good the case still is.

The SSK line is the reason this question has a cheap answer: a genuine GMT caliber in a Seiko 5 Sports case, sharing the 4R family's published $176 overhaul price.

42.5mm, 46mm lug-to-lug and 13.6mm thick, Hardlex and 100m. The 24-hour hand is set independently, which suits tracking home better than hopping zones.

The 4R34 is a caller GMT — the 24-hour hand is the one you set, not the local hand — but it is a real mechanical second time zone on a movement whose service price Seiko publishes.

The field-cased SSK023 puts the same movement in a 39.4mm case on a 20mm strap, which is the size most GMTs should be and very few are.

Everything else — 100m, Hardlex, three-year warranty, $176 overhaul — matches the SSK001. If you are unsure whether you will use the complication, this is the one you will still want to wear if the answer is no.

Identical movement and identical service cost to the SSK001 in a case 3mm narrower. If the 42.5mm SSK001 is too much watch, this is the same purchase in a size more wrists can carry.

The Nighthawk adds a second time zone and a slide-rule bezel to a 200m light-powered case, with Citizen's five-year warranty and no winding or battery changes.

Mineral crystal on a 42mm dial is the cost, and Citizen does not publish this reference's lug width. For a travel watch that you never service, it is a reasonable trade.

200m, five years of cover and a second time zone from a watch you never wind, service or open. The mineral crystal is the cost, and on a 42mm slab of glass it is a cost you will eventually see.