Best 3 tube preamps under $18000?

I will be pleased to know your opinion, about which can be the 3 best tube preamplifiers, with a price, NEW, under $18.000. I want to use them with SS amplifiers.
When using LA150MK2 SE for M60MK3.1 , which is better ? Single Ended RCA?
Or Balenced Ic ?

How about LA150MK2 SE+ M60MK3.1 vs. MP1+ M60MK3.1 for Merlin ?
Also,for Merlin VSM ,which is better ? Seperate (A150MK2 + M60MK3.1)?
Or Ars Sonum fila ?

Thank you !
I prefer the separates to the Ars. I like both the Joule single-ended RCA and the MP3, but if I had to choose I would proabably go with the Atma Combo, but the Joule is no slouch with the Atma M60s. I don't really feel qualified to tell you which you would prefer. If you had the Joule pre and the Atma amps, I would proabably stick with that.
The Messenger preamp is the finest I've owned and/or auditioned.

Disclaimer: mine is up for auction, but NOT for sonic reasons, I assure you.