I could never get that open and transparent tone from my X3. I liked it, but I like what I have now much better:)
As long as you are using a humbucker at the bridge, you can get that sound with just about any Marshall-ish profile. A Soldano might be a good starting point, too.
Throw clean boost in front of a plexi. Add some reverb. Done
It reminds me of a cross between "Lady Evil" Black Sabbath and "Looks that Kill" Mötley Crüe.
A couple of 'already close' rigs:
Andy's TAF 80s rig ( in the ones Kemper offers) would be a good starting point. Turn off the chorus ( I think it is on by default - in the 80s, we rarely turned them off)
For that matter, it wouldn't take much editing to make "Golub Crunch" sound like that, either.
If you have a hot pickup, the first step would be to turn down the gain on either of the above rigs.