BAT VK50SE or CJ Premier 16LS Series ll

I did not have the vk50se or cj 16ls, but we just compard the vk30se with CJ 17ls it is very similar to what you want test with ML 332 Cary CD 303 and BW 804 nautilus, from what I had been experienced with both pre-amp they are both beautiful in their own way but BAT it is neutral to warm sound and CJ more warmer and sweet romantic vocal and midrange is outstanding bat is quiet nice but not that sweet just did everything exactly from your source, I think it is down to preference choice once you are up here with all the fine equipments you have to let your ear decide which is the taste that you like. I would think if you have a SS amp and speaker that is neutral then bat will be the one, but if you have a bright SS and dry speaker like BWnautilus then CJ is a better match the only thing I did not like about CJ is they only used RCA no Balance. Tell us more what kind of gear are you using and may we can help with your decision both are great gear. Good luck and enjoy the music.

From my opinion, this is going to be great sell both of your amps don't run rotel with a fine Nautilus 802. Sell them both buying a ML 335 and CJ16LS or 17LS you will be set for awhile you will have both HI-FI sound a Musical sweet music , CJ will put out that analytical sound from ML and give you that sweet vocal and outstanding midrange.
You probably wondering why I did not mention anything about the bottom end because I know ML will drive that nautilus of your without any problem neither with CJ or BAT.