Aesthetix Collisto Signature or SLP 05 Preamp?

The Collisto Signature or SLP 05. Both can be found on the used market, and both are highly regarded and have excellent reviews

Both are tube preamps and one of them would be used in front of a pair of Cary 805AE (300B tube)monoblock amplifiers, pushing Vienna Acoustic Bethoven Concert Grand speakers at 91db. How do they compare? Any opinions out there?
I owned a Calypso and now have an SLP05. I don't know how the Callisto compares with the Calypso, but the Calypso cannot hold a candle to the Cary -- not in terms of sound quality, build quality, pleasure of use. This may not be much help, but my experience after owning the Calypso was that I preferred to go over to the Cary line than to move up the Aesthetix.
Cary pre,Cary amp,there's a natural synergy there.
I liked the Calypso OK but it was easily bettered by the PS Audio PCA-2. I think the Callisto is probably a better Linestage than the Calypso but I haven't heard it myself.
I have no experience with the Cary. However I have upgraded from a Calypso to a Callisto Signature. As good as the Calypso is the Callisto is in another league. If you have the space and the money I can't recommend it highly enough. Since I have gotten the Callisto I have had no urge to change a thing.

I hope some one has compared them directly. That would be interesting.

With Pre-amps.. I have been to hell and back. Now, I am in heaven. Another vote for Mr Had (Cary SLP)
I have also owned many of the top rated preamps from all of the usual suspects, and have settled in quite nicely with the SLP-05.