BAT VK50SE or CJ Premier 16LS Series ll

I have been auditioning preamps for quite some time. I’m basically interested in bi-amping my SS amps with tube preamps, looking to do this right the first time (yeah right! :) I’ve finally narrowed it down to these two fine tube preamps.

Balanced Audio TechnologyVK50SE

Conrad Johnson Premier16LS Series ll

Would anyone be so kind as to share any experiences they may have had with either of these preamps? Would anyone be able to provide a comparison of the two? Any info is appreciated.