Side by side

AVI-8 Flyboy Airmaster GMT AutomaticvsSeiko Prospex SPEEDTIMER Mechanical

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

AVI-8 Flyboy Airmaster GMT Automatic

Owners widely praise the AVI-8 Flyboy Airmaster GMT Automatic for its robust build quality, intricate three-timezone function, and crisp dial texture. The watch is noted for its wearable 41mm case size and 48.5mm lug-to-lug, with an internally positioned GMT complication that maintains a clean dial appearance. Some owners report the stock leather strap feels cheap and limits strap changing options. On balance, owners rate the AVI-8 Flyboy Airmaster GMT Automatic highly for its solid finishing and value, particularly highlighting the dial's depth and texture.

Seiko Prospex SPEEDTIMER Mechanical

The Seiko Prospex SPEEDTIMER Mechanical is praised for its visually appealing design and comfortable wearability, with owners frequently using its chronograph function for daily tasks. Reviewers note its clean dial layout and LumiBrite treated hands and markers, and one source highlights the 72-hour power reserve of the 6R55 movement. However, some owners criticize its chronograph functionality and the 24-hour subdial. On balance, owners and reviewers rate the Seiko Prospex SPEEDTIMER Mechanical highly for its daily usability and refined aesthetics.

At a glance

14 of 29 specs differ
Diameter
Flyboy Airmaster GMT Automatic40mm
Prospex SPEEDTIMER Mechanical39.5mm
Power Reserve
Flyboy Airmaster GMT Automatic40h
Prospex SPEEDTIMER Mechanical72h
Water Resistance
Flyboy Airmaster GMT Automatic50m
Prospex SPEEDTIMER Mechanical200m
MSRP
Flyboy Airmaster GMT Automatic$365
Prospex SPEEDTIMER Mechanical$995

Full specifications

Case

7 specs
Category
GMT
Chronograph
Diameter
40mm
39.5mm
Thickness
12mm
Lug-to-Lug
44.5mm
Lug Width
20mm
Material
316L Stainless Steel
Stainless Steel
Water Resistance
50m
200m

Crystal & Dial

3 specs
Crystal Shape
Flat
Curved
AR Coating
Inner
Anti-reflective coating on inner surface
Lume
None
LumiBrite on hands and index(es)

Movement

3 specs
Caliber
Seiko NH34
6R55
Power Reserve
40h
72h
Jewels
25
24

Pricing

1 specs
MSRP
$365
$995
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