You didn't say what the rest of your system is, other than speakers, and why you think you need an upgrade. As many have stated, the VK-60 is a superb amp. If you wanted to upgrade from that, you might want to somehow get to the VK75SE, slightly more power and keeping the magical BAT sound. Switching to SS, especially another brand, would require you to really listen first, to avoid making a mistake you might regret.
BAT vs. Mcintosh?
I currently own a VK-60 amp that I absolutely love but have often been intrigued by Mcintosh products. I will be able to spend about two thousand dollars on my next upgrade & have always considered purchasing another VK-60 but don't really have the room to run two of these massive amps based on the size of my listening area. Would I be better off trying a Mcintosh product, maybe a MA6500 or one of their other amps? I realize my VR4 jr's could use some more power which is why I'm considering the switch to a big Mcintosh solid state. I listen to clasic rock exclusively.