I dislike asking these types of questions but how strong is Robo-Ky compared to Ky in terms of swordmanship and combat prowess?
Depends on what version we're talking about, though I did cover Ky's bizarre relationship with Robo-Ky in a video not long ago.
In most instances, Robo-Ky has been one or several steps behind Ky in terms of physical prowess and skill... since the Scientists who manufactured Robo-Ky seemed to value battle data over practical knowledge advancement.
Here's a more varied example: when you take a photo... it's just a captured moment in time. It doesn't express an individual's full growth or potential, just what they were like in that singular moment.
That's the problem with Battle Data, it's static and doesn't consider the logical conclusion from beginning to end of how an individual will develop, even if its CPU has automatic updates... that's not the same as evolution of technique.
This is also why Robo-Ky as a series was discontinued in favor of Gear manufacturing, because Gears are biological specimens of a higher order and naturally evolve in combat by themselves as living creatures. It's why the Conclave agreed to work with the Valentines as well.
The Robo-Ky (Mk.III?) we saw in Revelator is probably the last of his kind, and possibly the most advanced compared to previous incarnations... he was said to even have self-sufficient components as well. But, in his case, he no longer makes an effort to surpass his “dame original” (Ky), because part of him became more human than expected.
You could say he was resigned to his fate of inferiority, but at the same time became a wholly separate individual from Ky Kiske.
It might very well be that because of this, he was able to defeat someone like Bedman with Venom’s help.