You should listen to the new Aesthetix Atlas amplifier. It's a hybrid amp with a vacuum tube gain stage and a SS output and driver stage (200watts into 8 ohms and double into 4 ohms). For me, in my system, it seems to bridge the gap between SS and Tube amplifiers. They also make a monoblock version that delivers double the power of the stereo amp. My previous amps were a Pass Labs 250.5 and before that Quicksilver V4 monoblocks.
BAT SS amps VS Ayre MX-R
I have a BAT VK-250SE with a VK-52SE preamp. I'd like to try a different solid state amp and eventually preamp to go with my Hansen Audio Prince speakers. I think the Prince's would benefit from a more high powered amp. I like the overall sound of the BAT equipment. I've considered the VK-600SE. I'm just alway interested in something different and maybe better. I'd like to hear form anyone with experience with either BAT or the Ayre MX-R amp or any other suggestions. With the Prince speakers I've left the upgrade path. I'm looking to do the same with my electronics. My front end is a Modwright Truth Transporter with Vintage tubes. I'm very happy with it.