Ratio FreeDiver Professional Sapphire RTFvsSeiko 5KX

FreeDiver Professional Sapphire RTF
RatioFreeDiver Professional Sapphire RTF

Ref. ratio-freediver-professional-sapphire-blue-sunray-dial-automatic-rtf0013-500m-mens-watch·MSRP $140

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Measurements

Catalog photos are all shot at the same flattering size. These aren't: every case below shares one millimeter scale.

Ratio FreeDiver Professional Sapphire RTF at true scale

FreeDiver Professional Sapphire RTF

Seiko 5KX at true scale

5KX

Diameter

42mm

42.5mm

Lug-to-Lug

n/a

46mm

Thickness

15.5mm

13.4mm

lowest

Water Resistance

500m

highest

100m

Power Reserve

n/a

41h

MSRP

$140

lowest

$350

Movement

Miyota 8215

Seiko 4R36

Case

5 specs
Diameter
42mm
42.5mm
Thickness
15.5mm
13.4mm
Lug-to-Lug
n/a
46mm
Lug Width
20mm
22mm
Water Resistance
500m
100m

Crystal & Dial

3 specs
Crystal
Sapphire
Hardlex
Dial Color
n/a
Blue
Lume
None
LumiBrite on hands and index(es)

Movement

3 specs
Caliber
Miyota 8215
Seiko 4R36
Power Reserve
0h
41h
Jewels
0
24

Pricing

1 specs
MSRP
$140
$350
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Reviews

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

Ratio FreeDiver Professional Sapphire RTF

Owners widely praise the Ratio FreeDiver Professional Sapphire RTF for its exceptional value for money. The watch is noted for its quality construction, with bezels described as having a great feel and minimal back play. One owner highlights an Abyss black dial, sapphire crystal with AR coating, and screw-down crown, built for daily wear with 200m water resistance. On balance, the consensus is that the Ratio FreeDiver Professional Sapphire RTF is a highly recommended watch due to its impressive quality and great price point.

Seiko 5KX

Owners widely praise the Seiko 5KX for its strong lume and value, with many reporting accuracy within +/-5 to 10 seconds per day, though some experience +/-1 second. The 42.5mm case is noted to wear smaller, and the watch offers a comfortable feel for many. Some owners are split on the bracelet quality, with opinions ranging from "cheaper side" with hollow links to "flimsy-feeling" jubilee. A few quality control issues have been reported, including a failed bezel clickspring and misaligned components. The Seiko 5KX is seen by some as a worthy successor to the original SKX, offering an upgraded movement with hacking and hand-winding capabilities, though others lament the loss of ISO certification and a screw-down crown. Overall, owners rate the Seiko 5KX highly for its excellent lume and value proposition, making it a popular choice for everyday wear.