Just curious, if you like your current tone so much why do you want to switch? What is it doing or not doing that you are seeking to change? If you identify what you want from the amp you aren't currently getting, you could find what amp would best deliver it.
All that being said, I loved the tone Al Cisneros got from his Green master volume unit and slaved power units when I saw Om. But that sound was a combination of his amps, the massive pair of 4x15's that (I assume) he was sending the lows through, the 4x10's he was (I'm assuming) sending the mids and up through, his choice of where and how to split the signal, his pedals, his Rics, and his fingers.