I play in a band that does the same type of music as yours. I might be in the minority, but I think one's bass, technique, and EQ have considerably more impact on one's sound; that's not to say amp/cab don't matter. I use GK with Markbass cab, but I wasn't happy with the sound I was getting from my Zon, so I got an Ibanez 1205E and am very happy with the variety of tones I can get now. From smooth fingered lines (e.g., Chic) to growling plucked lines (e.g., Slave) to crisp slapped lines (e.g., Cameo), I feel like it's all at my fingertips, as it were.
So, I'm basically suggesting you get whatever amp/cab combo you want and focus on your bass/technique/EQ. But whatever you do... keep it on the one!