GK (to me at least) seems very similar in sound to SWR: pretty hi-fi, a lot of high end, that type of thing. Depending on your style obviously, and your price range, would determine what would best fit you...
I know some people dislike the SWR workingman series, but for some odd reason ive always liked those more than their upper line stuff (especially the mo'bass, man that thing just doesnt like me...). Also the GK stuff would work well (you would think so, your using their cabs too..).
What kind of styles are you playing (both technique styles and musical styles)?