Strength
Raiden stoped arsenal gear
Grey Fox stoped rex
Raiden is stronger but was to stupid to just grab Snake and run
Speed
Grey Fox can doge/block bullets from Rexes dual gatling guns
Raiden strugled to block vamps knifes (whatch closely raiden has a few sticking out his chest)
Experience
Grey Fox obiously wins as he has the rank of "Fox"
Toughness
Raiden was nearly killed by vamp
Grey Fox was smashed by rex muiltiple times i think that Fox is tougher
these are if they were to fight similarly to the raiden vs vamp fight, same sword length and no guns or stealth.
i think that you got the toughness wrong, raiden is tougher, at least his suit is. he was being smashed by something much MUCH heavier than metal gear rex like 225 times as heavy, and that is being generous with rex's weight, and the minimum of arsenal. but...i do think that that doesnt matter much in this fight, as the blades obviously still penetrate it.
yeah, i think that fox takes it, but it would be an epic battle. they are both really well trained, have similar backgrounds (if you remember raiden was a child soldier too) i think that fox would probably be losing an arm or become impaled a few times, but would ultimately win.
toghness and strength are totally different raiden is STRONGER because he stoped arsenal but he was beaten to a pulp by vamp i think that fox could have easily taken that beating also raiden dosnt even manage to block all vamps throwing knives.
any way we are missing the point both of them can easily survive losing an arm or being stabbed in they end its down to thier speed if they can react fast enough to the other ones attacks I think that Fox wins on speed and experience
Vamp has physically restrained Raiden, is a casual bullet-timer, was much faster than MGS2 Raiden who was a Gatling Gun bullet-timer, and is virtually immortal.
ray is weak compared to rex. i know that ray was designed to take out rex, but you couldn't hurt rex until it opened its mouth, and making it do so was extremely difficult. with ray you can kill them, slowly it is true, by just shooting their heads, and making them open their mouth was easy.
rex has much better deffence than ray, also rex was being controlled by liquid, the stronger clone of big boss, while the rays were just being controlled by a computer.