ARC vs VAC preamp upgrade.....

Hi all,

I am considering upgrading my Conrad Johnson ET3SE preamp. Currently, my CJ ET3SE is connected to a Pass XA30.8 amp connected to Bowers and Wilkins 805D3 speakers. I like my CJ ET3SE, but believe I can improve clarity, tone, etc.

Want to stay with a tubed preamp. Considered ARC, CAT, Lamm, PrimaLuna,  PS Audio, VAC, and VTL. Would likely buy used, not new. Right now, leaning toward an ARC Reference (REF3, 5, or 5SE), or a VAC Renaissance MKV or Signature.

Recent CAT amps (Ultimate or Renaissance) are very hard to come by, though I would definitely be interested in one.

Lamm LL2.1 Deluxe seems like a lateral move, the LL 2 or 2.1 Reference is a hybrid (tubes only in power supply) so not really a tube preamp.

PrimaLuna has good reviews but not sure it is really in the same class as any of the others. 

PS Audio BHK has good reviews, but again not sure this is in same class as ARC or VAC.

VTL TL5.5 seems like a lateral move again. The TL 6.5  is a hybrid design, so not really a tube preamp.

I am primarily interested in views about the ARC versus VAC preamp choices from those of you that have direct experience with these two preamps. I would also be interested in input about my decision to exclude the Lamm, PrimaLuna, PS Audio, and VTL preamps.

Thanks in advance for all of your valuable input.