Art Audio Carissa Sig or Viva Solista Lt ???

I'm considering getting one of these 2 amps which both come w/ volume control and both are 845 variants. Anybody who doesn't live in the sticks like me who may have heard these 2 fine amps give me some feedback? I know both will drive my speakers fine. Just wondering which will get me closest to SET heaven.

Thanks all.
I haven't heard the Viva, but I own an Art Audio Carissa Signature and can tell you it's an absolutely superb amplifier.
Haven't heard the Viva, but I've owned the Carissa before. It's a nice amp, but I much prefer my Line Magnetic LM-518IA. One thing to consider about the Carissa is support as I'm not sure who the US distributor is.....if there is one.