BAT-VK31se or VK-50SE or LS17?


Guys,
I'm trying to buy a tube preamp to match with my Classe Ca-400. The system will drive a pair of Klipsch Horns

I narrow down my search to the following preamps
BAT-VK31se, VK-50SE, LS17

Please, chime in and let me know your choice.
jbony