After some time, I changed my mind about getting the orange Samurai. I am now leaning towards the orange 6R15 scuba. I have both the black Samurai and the 6R15 scuba and after wearing them for some time, I came to conclusion that the 6R15 scuba is a better and more desirable watch.
Movement – the 6R15 is clearly better than the 7S25 due to its ability to hack and handwind and its longer power reserve.
Lume – This is not a important factor for me but the 6R15 scuba has got brighter lume than the Samurai. This is because there is less luminous material on the rectangular markers on the Samurai to produce bright lume on par with that of the 6R15 scuba.
Size and thickness – I have no problem with the 45mm diameter of the 6R15 scuba. I also prefer 20mm strap to the 22mm ones that wears like a sweat band. As for thickness, the 6R15 scuba is quite thin for its size. I am neutral on this. In fact, I don’t mind the thickess of the 600m SD at all.
SS vs Ti – people can argue until the cows come home on the advantages of ss and ti but I like ss simply because it’s heavier. In my opinion, ss is the de facto material for traditional design like the 6R15 scuba. Ti is good for divers with unique design like the Samurai.