I am the guy with Amati and BAT VK-75SE. I have tried many amps, BAT VK-150 (non SE), ARC VT-100 Mk III, Sonic Frontiers Power 2, Rowland 501 (friend's), Accuphase P-450, Pass X-350, PS Audio HCA-2, and others that I can't remember. You know my choice. However, the 2nd runner up was not BAT-150 or ARC, it was Sonic Frontiers. In fact, another friend thought he would go for Sonic Frontiers given the price difference.
Where BAT excels is in the midrange purity and speed. From top to bottom, it's smooth and delicate but still has solid state like control. And like most tube amps, stage depth unmatched by solid state. Speed is another area BAT is better than most tube amps. But if you like romantic sound, BAT will not deliver.
Some other amps to consider, Jadis 845, Nagra, and CAT JL2.