It’s a battle of wits in this round as two A.Is take each other on. Leela (UESC) was able to crash the tech of several planets while Skynet was content to humiliate and exterminate the humans. Skynet seems to be better at predicting human actions and taking over Earth’s weapons was pretty impressive. It would be difficult for either one of these fighters to take over the other one, but I would say that Skynet has better offensive capabilities, which should grant her/him/it the win. Skynet wins.
DReager1.com 
All of her efforts on the Marathon were to prevent. the takeover by the Pfhor, so I think that her defense is excellent.
I agree that Leela didn’t seem very offensive until she went rampant and took over the 14+ planet network.
Leela is definitely rock solid on defense so it would be a long clash between titans. I am confident that Skynet would be able to eventually pull through thanks to Earth’s primitive yet very destructive tech. It’s usually downplayed, but we have some pretty epic tech on Earth. Taking over that network was definitely a really impressive feat for Leela
If Skynet led the Pfhor assault on the Marathon, would it have been destroyed?
Yes, once Skynet sets its sights on something…it’s over!